


Your Cheating Hearts

by TheseusInTheMaze, zaffrin



Category: Doctor Who (2005)
Genre: Because it's O, Cheating, Deception, Dubious Consent, F/F, F/M, Infidelity, Jealousy, who's really the Master
Language: English
Status: In-Progress
Published: 2020-12-15
Updated: 2021-01-16
Packaged: 2021-03-09 22:08:47
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 8
Words: 29,995
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/27783499
Author URL: https://archiveofourown.org/users/TheseusInTheMaze/pseuds/TheseusInTheMaze, https://archiveofourown.org/users/zaffrin/pseuds/zaffrin
Summary: The Doctor miscalculated and left the fam for a longer period of time than she intended. While she was away, Yaz and O got engaged. Now she's back.
Relationships: Thirteenth Doctor/O, Thirteenth Doctor/The Master (Dhawan), Thirteenth Doctor/Yasmin Khan, Yasmin Khan/O, Yasmin Khan/The Master (Dhawan)
Comments: 43
Kudos: 72





	1. Chapter 1

**Author's Note:**

> This fic has been co-written by TheseusInTheMaze and Zaffrin. We hope you enjoy!

The Doctor rocks on her heels, and tries not to pace around the console room.

Okay. So it’s been a bit of a mess, escaping the Kasaavin had been a right pain, and then she had lost track of the Fam, but she’s gotten a transmission from O letting her know that all is well. And okay, maybe it would have been a little simpler to go to Yaz's flat and knock on the door, but. 

Well. 

She’s still a little intimidated by Najia. It’s normal, because her companions' mums always seem to have it out for her. 

So it makes perfect sense to just triangulate on Yaz in the right year and land, and then she can apologize for buggering off. Maybe she’ll get ahold of O too, see if he'd want to join the Fam for a bit of sightseeing. 

There is a movie playing in the other room, and the Doctor can hear the soft sounds of humans… humaning. Gentle laughter, talking. Oh no. Maybe she’ll have to deal with Najia after all. But at least the TARDIS is _right_ there, and she’ll be able to grab Yaz, abscond off into the TARDIS. 

She’s been getting… weird, without her human companions. It had been for their own good when she sent them off, and the Doctor had managed to sort everything out with minimal violence and even more minimal theatrics. All in all, a win. And maybe she is off by a bit (but just a _bit_ ), but that will be fine.

She stops dead in her tracks when she rounds the corner, into the living room.

That is… Yaz’s back. Yaz’s back, covered by a shirt, and that is significant because Yaz’s lower half is _not_ covered by a shirt. Is not, in fact, covered by anything. Yaz’s backside is very round and look very firm, the skin very soft. The hands holding it open are giving the Doctor a rather perfect view of the cock that is sliding into Yaz’s cunt, and oh, but that is. 

Well.

It is pink, inside. The cock that Yaz is riding is opening her _wonderfully_ , and the Doctor remembers what it was like to have her own cock, what it felt like pulsing inside of a scaldingly hot human body, the way it was squeezed, the way that spooky singular heartbeat seemed to take up the whole world. She bites her lip, her hands balled into fists, as Yaz moans.

There is a wet sound - a different wet sound from the noises that Yaz’s cunt is making, as the wonderful, beautiful human woman is kissed by her mysterious paramore. And then they break the kiss, and Yaz bows forward, Her hair falls away from her back, over one shoulder, and the Doctor can see the delicate, vulnerable curve of the back of her neck. 

The person fucking Yaz pulls her closer, and then their eyes meet the Doctor’s, and the Doctor freezes. 

It’s O. She’d know his face anywhere - she’d even know that _iteration_ of his face, because she remembers what it had looked like, over her own. That night in the Outback, when he’d kissed her so sweetly, his cock sliding into her carefully, his fingers nervous on her face. 

_Fuck_. 

She swears she sees O’s eyes _gleam_ for a split second before he blinks, and flounders, spluttering out a “ _Doctor_!” In a voice that was something close to a squeak, and the glint must have been just a trick of the light. 

“What!?” Yaz stops moving, O is still staring at the Doctor, and the Doctor is still staring at O, and Yaz, and where O and Yaz are joined and -

Oh, this is all going to be very awkward isn’t it? 

“Sorry!” She manages, whirling on her heel. “Sorry, I -“

“ _Doctor!?_ ” Yaz’s voice this time, and she sounds very alarmed, very very alarmed and shocked and it wasn’t _that_ much of a surprise that she’d just landed in her room was it? Until the Doctor suddenly realises that this _wasn’t_ Yaz’s room, nor was it Yaz’s family’s flat (she wouldn’t forget that sofa), and Yaz was clearly - _clearly_ \- very busy and…

Oh, so yes, perhaps it had been a bit of an assumption to just drop in on her like this, she should have called first, makes a mental note to do that in future. 

The Doctor processes all this very fast, remembers that there’s two rather undressed people in the room behind her - then remembers that those people are Yaz and O - _Yaz and O_ \- and that she’d just had a very clear view of what Yaz and O were doing (Yaz and _O!?_ O, who the Doctor had done the very same thing he and Yaz were currently doing with not two days prior, and Yaz who the Doctor had definitely had more than the odd stray thought about doing the same thing with once or twice too -) and decides that yes this situation is going to be very awkward on all levels. 

“Doctor, what are you _doing_ here?” Yaz’s voice is rough, almost squeaky. There’s the sound of rustling.

“Well,” the Doctor said, “sorted out all the business with the…” She tries to remember the name of the aliens, but all she can think of is the bow of Yaz’s back, the way O’s fingers dimpled the flesh of Yaz’s arse. _Did it look like that with me, when he did it with me? I remember he grabbed my thighs._ She presses her thighs together, arousal pooling in her guts. 

“The Kassavian?” Yaz prompts. She’s coming into the next room, and she’s wearing a pair of joggers now. She still looks tousled, her lips swollen. The Doctor can smell the pheromones heavy in the air. “I’ve been worried sick, Doctor!”

“Oh.” She scratches at her face. “Sorry. All good though, no need to worry!” She says, pasting a smile on her face that was a bit too forced and bright. 

“All…” Yaz is in front of her now; and her brow is furrowed, a deep line of worry and confusion etched into it as she shakes her head. “Doctor… where have you been!?”

“Been? Nowhere! Just sorted all that business out - got thrown back in time a century or two but everything worked out in the end!” The bright smile fades from her face when Yaz’s doesn’t match it. She glances over at O, sitting on the couch (also more dressed than the last time she’d looked), and his face matches Yaz’s. The Doctor glances between them, blinking.

“Is something wrong?”

“ _Something -!?_ Yes - something’s wrong!” Yaz exclaims, and her voice is shrill, an edge of hysteria to her words the Doctor hasn’t heard before. She takes a step back, startled. “How could you do this?”

“Do what?”

“ _Eighteen months,_ Doctor! No call, no text - we’ve both tried to reach you, over and over! You just _vanished!”_

The Doctor’s mouth falls open. She glances at O. Dread is settling in the pit of her stomach, and she’s reminded sharply, horribly, of another time, another life, another girl… except that time she’d taken Rose with her. She’d left Yaz. Yaz thought she’d left… her whole fam did. “I… it’s been eighteen months?”

O stands from the sofa and crosses the room. “Yes, it has,” he confirms, stopping next to Yaz and putting his hand on her back. The Doctor’s eyes follow the movement, watch as the hand rubs over her before dropping to link with Yaz’s own, their fingers weaving together. Something catches the light, and the Doctor’s eyes widen.

 _“...Oh,”_ she says.

Yaz glances down at her hand where the Doctor's wide eyed gaze is settled, and quickly pulls it from O.

“Oh… yeah,” she says, and when the Doctor looks back up her cheeks are tinted pink. The engagement ring is tucked out of sight behind her back. “A lot’s happened since you’ve been gone,” she says quietly. 

“I see,” the Doctor says, and something feels weird in her tummy, heavy and thick where the dread had settled and not dissipated. “Well.” She forces a smile. “Congratulations are in order!”

“Yeah…” says Yaz, and glances at O, then back at the Doctor. “I just…” something flickers across her face, and she moves as if she’s going to make forwards then hesitates. “I didn’t know if I would ever see you again…”

The Doctor’s face softens. “Yaz…”

And then abruptly she has an armful of dark-haired girl, a nose pressed into her neck, arms wrapped tightly around her back and a warm body pressed against hers - a warm body that was, the Doctor remembers rather abruptly, not five minutes ago pressed against another warm body, one which happens to now be standing three feet away and god, she can still smell him on her, his aftershave and that distinctive scent that was O, that the Doctor remembers from being pressed up against it herself all night just recently and -

“I was afraid,” Yaz says, and her voice is thick with tears. Her hair still smells like sex and sweat, and _what if I kissed her right now?_ flashes through the Doctor’s head. “I was afraid I’d never see you again, and Oliver-”

“Oliver,” the Doctor interrupts, glancing over at O, “Is that your name?”

“Yep,” says O - says _Oliver_ , and he looks sheepish. He takes a step closer, as if he’s not sure if he’s allowed to come closer. 

On impulse, the Doctor opens her arms, and he steps closer, until he’s hugging her too, and she’s got the two humans pressed against her. Two hearts, warm bodies pressed into her own, and she can smell their pheromones, their sweat. They still smell like sex, and she can feel the slickness from their exertion under thier clothes, making their shirts stick to their backs. She rubs their backs, and she holds them in her arms, trying to ignore the arousal in the pit of her stomach and the anxiety climbing up the back of her throat. 

“I’m so sorry,” she says, and then she takes a step back, so that she’s looking them both square in the face. She’s still holding their hands, and when did that happen? Their fingers are linked - she absently runs her finger over the stone on Yaz’s ring, wiggling it this way and that. Oliver is holding on to her so tightly, as if he’s afraid he’ll lose her if he lets go. So is Yaz. 

Yaz’s face is damp, her eyes red. It makes the Doctor’s two hearts _ache_ , and probably leads to what she says next.

“You two should come with me,” she says. “As an apology.”

“What about Ryan and Graham?” Yaz asks, frowning. 

“They’ll get their make up trip too,” the Doctor says, and she lets go of their hands, spinning on her heel again. “Been a while since I had a couple on the TARDIS. It’ll do the old girl some good, havin’ some affection about the place.” She clears her throat, rubs her hands together, and looks over her shoulder at them. “What d’you say?”

Yaz and Oliver are sharing a look that she doesn’t understand, and she _hates_ that - she’s never been one to appreciate being left out of a secret, let alone between two humans. Between _her_ humans, although she shouldn’t think of them like that but… still. 

When did they get to the point that they could share looks like that? What has she missed? 

“One trip can’t hurt,” says Oliver, and he’s giving Yaz a look like a kicked puppy. “I’ve always wanted to see more of the universe.”

Yaz’s mouth twists, as if she’s not sure how to respond. Then she nods. “Alright,” she says, “but we _do_ need to get back on time.” She smiles, and the smile is… mostly genuine. “Don’t want to miss our own wedding!”

“I’m sure they’d wait for you,” the Doctor says. “Can’t have a wedding without the happy couple after all! Or trio. Or… well, in the future, there’s lots of options, really, but we don’t need to worry about that, since it’s just you two. You two gettin’ married. Love a wedding, me. Hope I’m invited.” She opens the TARDIS doors, strides in, and she is aware that her mouth is going without her brain being involved.

“We just need to pack up,” Oliver says, and he leans into the TARDIS, his expression as gobsmacked as the first time. “We’ll, uh, we’ll be right along. Please don’t leave without us.”

“Wouldn’t dream of it,” the Doctor assures them. “I can stay parked for a bit while you sort out the… whatnot.” She makes a vague hand gesture to the room outside the TARDIS, with its big bed and chest of drawers. 

“We’ll be right along,” Oliver says, and he takes Yaz by the hand and pulls her into the next room. They’re probably going to have a proper talk about… something. Something that isn’t the Doctor’s business, as much as she wants to know. 

_I wonder if they’re going to finish what they were doing?_ The Doctor thinks, as she pulls her welding goggles on and goes to find that one tricky spot on the console. She is very carefully not listening for the familiar sound of human moans, gasps, wet sounds…

Her boxers are sticky against her thigh, but she can ignore that too. She just needs to concentrate on fixing this one tricky lever, and not thinking about what she’d seen with those two _very_ attractive humans. 

_Eighteen months._. Nice one, Doctor, she thinks, rubbing a hand over her face in frustration. It wouldn’t be the first time it had happened, but it never stings any less. To just… lose time like that in a blink. Time with her friends. _Precious_ time. And it was made even worse with the knowledge of them not knowing where she’d been. 

She thinks of the glint of that ring on Yaz’s finger, and the Doctor doesn’t know if the odd heavy feeling in her gut is due to the fact that her friend’s lives had carried on without her or… something else. She’s happy for them. Of course. Yaz and O were both brilliant humans - she’s happy that they could find happiness together. With that resolve lodged firmly in her head, the Doctor hastens to busy herself until they join her.

-*-

“I can’t believe she’s back,” Yaz says for the third time, flopping down onto her back on the bed as O pulls some more respectable clothes out of the cupboard for them. 

“We did always know it was a possibility,” he replies easily. “I know you’ve been worried - but I have told you all along it was more than likely that she just lost track of time, or got her dates muddled.”

“It’s easy for you to believe that,” Yaz sighs, “She’s popped in and out of your life for years. The Doctor… was my life, before she vanished.” She looks round at O and her gaze softens. “Before you came along,” she hastily adds. Her fiance offers her a smile, and tosses the sweater in his hands to the bed before crawling up onto it with her. He leans down over her, one hand delving into her hair and mouth hovering over hers as he brushes his nose against Yaz’s. Her eyelids flutter shut as he leans down to kiss her, and she tries to forget, for a moment, that the Doctor’s back and everything has changed in the blink of an eye. 

She makes a sound against O’s mouth when his fingers tug at the waistband of her joggers.  
“O,” she blinks up at him as she pushes him back. “What are you doing? We have to get to the TARDIS.”

“I know but… she’ll be busy in there, you know what she’s like…” his soft voice drifts off as his mouth moves to Yaz’s neck, and she bites her lip, trying not to think about the fact that the Doctor is just inside her TARDIS in the next room to them as she lets O ease her jogging bottoms off. 

“We shouldn’t,” she utters, as O takes her hand in his and presses it to the bulge in his own trousers. 

“Please Yaz,” he breathes against her skin. “I was so close when she showed up… don’t know if I can last the day without this… it might not even be a day, you know what trips with the Doctor are like, could be a week before we get the chance again…”

Squeezing him gently in her hand, Yaz’s eyes slide closed as he kisses and nips at her neck, his other hand stroking between her legs. She’d been so wet and open with him moving inside her just ten minutes ago, and his fingers slide easily though her slick flesh, until his words sink into her head, and her eyes snap back open. 

“What? How do you know what trips with her are like? I thought you said you’d never been in the TARDIS before we went to that party…”

O’s fingers pause, and she swears he inhales sharply against her, before he is lifting himself up to look down at her, and watching her face carefully with a soft gaze as he sinks two of his fingers inside her. “I haven’t. But you’ve told me enough stories.”

“Oh,” she utters. 

“You feel good,” he breathes, caressing her inside, stroking her inner walls steadily with a come-hither movement that has all the muscles low in her body tightening. His thumb finds her clit, and wetness rushes to meet it. 

“Fine,” Yaz breathes out, squeezing him before her hands hastily go to fumble him free of his trousers. “But it’s gonna have to be quick…”

Her fiance grins down at her, face delighted as she works him free, and he can ease his fingers out of her to line his cock up with her entrance instead. 

“Whatever my love desires…” He breathes, before he presses into her, and Yaz’s eyes drift closed again feeling herself relax around him as her body accepts him inside, and she tries very, _very_ hard to focus on _him_ , and not think about the blonde haired woman just meters away from them both right at that moment.

She comes harder than she has in a long time. 

_-*-_

**Notes for the Chapter:**

> More chapters to come! ;)


	2. Chapter 2

The humans are both flushed when they come back into the TARDIS. Yaz is walking easier, with an open stride- it's clear she just had an orgasm. O - Oliver, she needs to remember his name is _Oliver_ seems to have lost some of the tension around his shoulders. They're both carrying suitcases, and look… the Doctor can't entirely read their expressions. 

"I'll let you get settled in," the Doctor says brightly, pushing her welding goggles back up her face. "Where d'you wanna go?"

"Someplace that isn't like Earth," Oliver says. "Yaz might be an old hat at space travel, but I've been fully stuck on Terra Firma." His face is open and honest, all wide, beautiful eyes staring into the Doctor's face. 

_I want to kiss him, right here_ , the Doctor thinks. She glances over at Yaz, sees her friend looking at her with an expression of trepidation mixed with hope. _It would break her heart, and I've already done enough of that_

"Well, I can't promise there won't be any terror," she says, deliberately flattening the last "r" to force the pun through. 

"Oi," Yaz says, and then she's giggling, her whole face opening like a flower, and then Oliver is laughing as well, and some of the leaden weight that's been sitting in her guts seems to disappear 

Things are going to be alright. 

-*-

Some hours later, Yaz approaches the Doctor, and tries to ignore the anxiety that's making her palms sweat. 

The Doctor is… herself, as always. On her knees and up to her elbows in the guts of some TARDIS component. 

"Doctor," Yaz says, and the other woman looks up and smiles. 

"Hullo, Yaz," the Doctor says. "Has Oliver given any thought to where he wants to go? He mentioned wanted to see the Horsehead Nebula in person _ages_ ago, were wondering if that were still true."

Yaz is faintly surprised at the brief flash of… jealousy? The Doctor has known her fiance longer than she has, and possibly knows parts of him better than Yaz ever will. 

She shoves past that - she'll deal with it later. "Actually, wanted to ask you something else," she said. She clears her throat. "Oliver is in the kitchen with all the blenders," she says, "and um. I need a new room."

The Doctor frowns. "Do ya? What's wrong with the current one."

"Bed isn't big enough," Yaz says, and her cheeks are turning very pink. "TARDIS keeps offering us other rooms, but all with twin beds."

"Oh," says the Doctor. She extracts her arm from the guts of whatever she's been fiddling with. "You used to be good with the twin bed."

"Used to just be me, alone," Yaz says. She's still blushing. 

"Oh, I were meaning to talk to you about that," the Doctor says, and she stands up, dusting the soot off of her coat. "Are you on birth control?"

"Excuse me?" They can't be having this conversation. 

"When I saw you and O, um…" The Doctor trails off, clears her throat. "I noticed you weren't usin' a condom, and that's fine outside the TARDIS, but babies conceived in the TARDIS get… weird, and I don't wanna have to put a moratorium on all sex but - "

"Got an IUD," Yaz says, before the Doctor can continue. "You, uh, you don't need to worry. About that."

"Excellent," the Doctor says, rubbing her hands together. "You lot are free to fornicate to your hearts content, then!" 

_I want the ground to open up and end me_ , Yaz thinks dazedly. "Is there a way to get a bedroom with a bigger bed?" Yaz asks, dragging the conversation kicking and screaming back to its origin point. 

"Go up two flights of stairs from your current room," the Doctor says, "should be good to go." 

"Right," Yaz says, and she turns on her heel to walk out before she can further die of embarrassment. "Thanks," she calls over her shoulder. 

"Think nothing of it," the Doctor calls back. 

-*-

She doesn’t mean to listen to them.

The adventure was great! There were zombie unicorns (... sort of, it was complicated), there was a revolution. O had gotten to explode a bridge, Yaz had rallied the troops, and the Doctor had given a very good speech.

And now… the three of them are back on the TARDIS. The two humans have their own room, and the Doctor was up to her elbows in the TARDIS console when she’d remembered that the TARDIS didn’t always give people clean towels. And she doesn’t want them to go without towels!

(And okay, maybe she’s feeling guilty for spying on them, and for dragging them through this whole debacle, and because she’s missed them, and humans get weird about her just showing up for no reason). 

She sees the door open, and she’s about to walk in when she hears the moan. There’s a split second of panic - _is someone in pain?_ \- and then she remembers the sight of the two of them on their couch. 

_She’s got an IUD,_ she thinks. _I don’t need to worry. They’re allowed their privacy._

So why is the door open?

“Oh,” Yaz moans, or is it _O_ , as a name? Her voice goes a little high pitched - _what’s he doing to her?_

The Doctor isn’t looking around the edge of the door. She’s made a point of not looking, she’s just… pausing. She can hear them moving, can hear the bed creaking, can hear the wet sounds and the way the creaking is getting louder and louder, 

“I can’t… believe we’re doing this… here,” O gasps out, and there’s a grunt, and then, “ _fuck_ , Yaz, do that again, _please_!” 

_I remember having a cock,_ the Doctor thinks wildly. _I remember pushing it in a girl. Is he pushing it into her, or is she riding him? I know she likes riding him. Or does he like her riding him? Should I ask?_

That isn’t a thing to ask, is it? 

How to even start that conversation?

There’s a long, drawn out groan, and then the sound of the two bodies falling together. The soft sound of kissing. 

She tiptoes away, opening the door closest to her once she’s down the hall and sidling into the old disused bedroom. There isn’t any dust - as if the TARDIS would _ever_ allow dust to build up - but it still has a feel of someplace that hasn’t seen people in a long time. She flops onto the bed (was this Sarah Jane’s old bed? Or maybe Jo’s?) and she shoves a hand down the front of her trousers. 

She keeps her eyes closed when she comes, and she can pretend that she isn’t thinking about the curve of Yaz’s back, or sounds O makes as he comes. She can pretend she isn’t thinking of the two humans in the guts of her TARDIS, as she comes against her own hand. 

-*-

“D’you think the TARDIS minds?” Yaz asks, as she and Oliver lie in a sweaty tangle of limbs, legs intertwined.

“Mind?” O’s fingers are stroking along the line of her spine, and goosebumps are erupting like crocuses popping out of the snow. 

“Like, that we’re… y’know, foolin’ around inside of her. Since the Doctor talks about the TARDIS like a person, even got me doin’ it. Calling it ‘she’.” She sighs, as one ticklish finger circles around the shell of her ear, plays with the wispy hairs covering her temple. 

“I dunno,” O says, and with her head on his chest like this, she can feel it vibrate through her skull, his chest hair ticklish against her cheek. “The Doctor would’ve told us not to do anything like that if it was a problem, I should think.” 

She sighs, another ticklish breath across his chest, and her eyes flutter closed. “You’re probably right,” she murmurs, and she snuggles in a little closer to him, hooking one leg around his. Her thighs are still sticky with his come, and she’s wet and open from him. 

It’s still _surreal_ to be here, with him, knowing the Doctor is off somewhere fiddling with the TARDIS. Her life has been delineated before that - the time when she traveled with the Doctor, the time when she was with Oliver. And now… she’s here with the Doctor, and with Oliver. it’s like going to her primary school classes as an adult, or looking at pictures of herself as a child in her work uniform. Two parts of her life, inexplicably bound together. 

She’s still pondering this, as she falls into a gentle doze, soothed by the beat of O’s heart.

-*-

The Master sighs, letting himself relax. The bio-damper he’s been using to disguise his second heartbeat is like a song circling his head, and it’s a relief to let it go. He wriggles out from under the human carefully, letting her snuggle into the warm spot on the bed. Her fist is tucked up under her chin, and the blankets are around her waist. 

She’s snoring quietly, and he can almost feel something like tenderness, if he tries to find it. He doesn’t want to find it. 

He wraps himself in a fluffy robe, slips his feet into a pair of thick socks. He pulls a pair of joggers on too, considers a sweater, then discards it. He’s going for vulnerable, approachable. Soft. He knows the Doctor can’t resist soft. 

He still can’t believe Yaz didn’t notice the open bedroom door. He should see how much further he can push it. 

He finds the Doctor sitting at a table, a glass of orange juice in front of her. She isn’t wearing her coat, and her sleeves are rolled up, the cuffs neatly tucked right under her elbows. She looks up at him, and he _knows_ that she was there - he could smell the flare of her arousal, even under the misting of human pheromones he’d been drowning in. Her face is flushed, and she looks at him with an almost _guilty_ expression. 

He smiles at her, putting on his best _ain’t-I-harmless_ expression, and he makes a show of closing the robe over his bare chest. “Didn’t realize you’d be up,” he says, indicating the chair in front of him. “Mind if I join you?”

“Go for it,” the Doctor said, and she smiles at him. The expression is forced, and her gaze keep darting from his tousled hair to his bare chest to his lips, which are probably still swollen from kissing Yaz. “You two settlin’ in alright?”

“Oh, definitely,” the Master says, and he rests his elbows on the table, his chin on his palm. He yawns, rubs his face. “Sorry, just, uh, just winding down.” He clears his throat, blushes, looking down at his hands, then back up at her. 

He catches the pink tinge of her cheeks, and some inner part of him claps and cackles. _Got ya._

“You and Yaz,” the Doctor says, “are you… are you happy? Together?” The Doctor jiggles her leg. “Because you’re two of my favorite humans, and you both…” She trails off, looks at her hands, looks at his face again. “I want you to be happy,” she says, and the words seem to peter off. 

“Doctor,” the Master says, and he keeps the eye contact, lets his robe fall open as he reaches a hand out to cover her own, “I can promise you, just having you in my life - in _our_ lives - makes us very happy.” 

Her eyes dart down - she’s never been a subtle one, has she - and then stare into his own. He makes them limpid, open, projects all the sweetness and kindness that he can muster. What would O say at a time like this? 

“Does it bother you to have us here?” He stands up, and his joggers are slung low, showing the vee of his hips. He’s not used to being on _display_ like this, but he wants to see the morally upright (ha!) Doctor crack. 

“Why would it bother me?” The Doctor leans back in her seat, and he hears the chair creak as he gets himself an apple from the fridge, then sits back down.

“Well…” He takes a bite of his apple, and _crunch_ is very loud in the quiet kitchen. It feels a little bit as if the little room, with its blinking fluorescent lights, is its own little time vortex, and nothing else exists outside the golden light. “I know it can be… lonely.” He takes another bite. “Seeing a couple, when you’re not in one.” 

The Doctor takes a swig of her orange juice, tilts her chair back a little farther. “Oh, I don’t work that way,” she says cheerfully. 

_LIke Hell you don’t_ , he thinks. “So…” He clears his throat, looks over his shoulder as if he’s guilty. “So that night… together, was that -”

“No,” the Doctor says quickly. “No, no, that was… that was nice. Enjoyed it immensely. One of the nicer nights of my life in the Outback, trust me, very nice, I just…” She stands up, finishes her orange juice and puts the glass in the sink. “I’m off to do more repairs,” she says, and she jerks a thumb over her shoulder. ‘One of the filtration systems is gummed up. If you need to find me, come ask the TARDIS.”

“Will it be able to find you?” He takes another bite of his apple, and the sweetness seems to explode across his tongue like a firework. 

“Oh, definitely,” the Doctor says. “She can always find me.” 

“I have faith that I’ll be able to find you,” the Master says, and he doesn’t know if he’s saying it as himself or as the stupid human disguise he’s wearing.

She breaks into a slightly sad smile, and she nods. “Goodnight, O,” she says, and she makes her way down a corridor. 

-*-

She had _intended_ to head down to one of the TARDIS engine rooms just like she’d told O, but she gets a whiff of Yaz’s pheromones as she heads down one of the corridors and her feet take her in a different direction, until she’s standing in front of the same door she’d peeked round earlier. It is still open, and the human girl is slumbering on the bed in a pile of rumpled blankets, lit softly by a lamp in one corner. One bare leg is slung out over the covers, and her dark hair is splayed across the pillows. The Doctor blushes slightly when she thinks back to the cause of her rumpled appearance. 

Her fingers curl into the doorframe, and she leans against it, unable to tear her eyes from Yaz. A year and a half had passed in a blink for her, and although she was here somehow… the Doctor can’t help but feel like she’s lost her. Yaz isn’t _hers_ anymore. Not that she ever was - not that she was belonged to Oliver now, per se, it’s just that… Yaz was special. She loved her fam, but Yaz was always the one the Doctor thought would stay with her, when the others inevitably left. Graham wouldn’t want to travel forever and Ryan has his own life and friends in Sheffield. He talked about them a lot - she had noticed that Yaz never spoke about her friends. The Doctor didn’t know if that was because she didn’t have any, or whether they were just less significant in her life. But either way… Yaz had been hers, in a sense, as much as they ever were, and now she was lost. 

Sure, Yaz was here now, on the Doctor’s TARDIS, but it won’t last. Yaz and Oliver are getting married, and then they’d want their own life - settle down and all that, procreate… she repressed a shudder at the thought, unable to put her finger why the thought was so distasteful to her. 

She gets the same twang in her chest when she thinks of O too. He’s been hers also… she’s known him so long, and been so used to him always been there at the end of the phone whenever she fancied a chat, always answering her instantly, like he was just waiting for her message or call. She supposes that would change too. He’d be busy - with Yaz. She supposes it was never fair of her to take it for granted so in the first place.

Yaz stirs in her sleep, and the Doctor quickly darts back round the corner. She hears her give a yawn, and the rustling of the covers, like someone sitting up. Taking a few steps back, the Doctor pauses before striding forward like she’d just come from down the corridor, and rapping her knuckles on the open door.

“Oh! Doctor,” Yaz sounds surprised when she sticks her head round, and scrambles a bit, sitting up straighter.

“Hiya. Didn’t wake you did I?” She says, wandering in, hands in her pockets.

“No, just woke up actually…”

“Oh right, good,” the Doctor nods.

“Was there… something you needed?” Yaz prompts as the Doctor noses round her - their - room, and when she glances over at her she looks a little uncomfortable, clutching the duvet to her chest. - _Right._ Naked. Post sex. In the bed her and O had had sex in just an hour ago. The Doctor’s cheeks flush a bit and she decides to make this quick.

“No nothing, just checking everything’s ok with your room now?”

“Oh - yeah. The room’s great, thanks Doctor.”

Neither of them mention that Yaz is now sleeping on an entirely different floor of the TARDIS, with big rooms, and Yaz is blushing as she avoids the Doctor’s eyes, fiddling with her hair.

“Well. Good. Great. Good then.” She nods firmly. “Suppose you’ll be off to sleep for a bit.”

“Yeah, I am pretty tired…” Yaz says, her eyes catching the Doctor’s on that word, and jumping away again quickly, cheeks flushing in a way that’s obvious they’re both suddenly thinking of the reason she might be tired.

Not that she knows the Doctor knows that, of course. Although perhaps it would be obvious to anyone from the er… ack of attire and… rumpled-ness…

“Right!” The Doctor says brightly, and claps her hands. “Good! Night then!”

“Goodnight Doctor,” Yaz replies softly, and she shoots her a thumbs up (a _thumbs up, Doctor? Really!?_ ), before darting back out the open door. 

She closes it behind her this time, and lets herself sag against it, rubbing a hand over her forehead.

It will be fine. She just… needed to get used to it. The idea of Yaz and O as a couple - they’d had eighteen months to settle into it, it was just the surprise to her, that was all. 

Nothing else.

**Notes for the Chapter:**

> This whole fic could just be replaced with the word "guilty horny pining" written over and over again, I swear.


	3. Chapter 3

Later that week, the Doctor knocks on the door to Yaz and O’s flat, and rocks back on her heels while she waits, listening to the sound of footsteps inside.

Dark surprised eyes greet her when the door swings open, and O blinks at her. “Doctor! I wasn’t expecting you. Was I?”

She shrugs. “I don’t know, were you?” She frowns, wrinkling her nose. “I said I’d be back soon, and it’s been… what, four days? Five?”

“About a week,” O says, and she relaxes a bit. So it hasn’t been that long. 

“So what’re you and Yaz up to tonight? Fancy a trip to the New Niagara Falls?” She shoves her hands into her pockets, takes them out, taps one foot. “Better ‘n the old Niagara Falls. Or we could go to the old Niagara Falls. Did you know they turned it off once? Well, sort of, not like you’d turn off a tap, but… still.” She trails off. “Where’s Yaz?” 

He chuckles. “Uh… Yaz isn’t home. Working a late shift tonight.” He makes a sheepish face. “Sorry.” 

“Oh. Right,” she says, ignoring the way something flips in her stomach at that. “Can I come in?”

“Of course!” He stands back, gesturing her inside. 

“When’s Yaz due home?” The Doctor kicks her boots off next to theirs on the mat, hangs her coat up on the hook. She feels faintly naked without it, and she tries to ignore that. Tries to ignore the odd mix of disappointment at not seeing Yaz, and the excitement at being alone with O again. 

“Late,” O says. “She’s workin’ a double for a mate.” He looks around the room, and seems slightly embarrassed. “Sorry, if I’d have known you’d be comin’ to visit, I would’ve…” He trails off, looking faintly sheepish. The Doctor can see files scattered about on all the various flat surfaces, and a mug of tea on the coffee table. “Tidied up,” he finishes.

The Doctor flops onto the couch, stretching her legs out in front of her. “I don’t wanna interrupt your evening,” she says, even as she gets comfortable. “I can head off -”

“You’re always welcome here,” O interrupts, and he gestures at his laptop. “I was about to order dinner. There’ll be leftovers for Yaz, would you like anything?”

“Oh, definitely,” the Doctor says, and she sits up, reaching for the remote on the coffee table. “Watchin’ anything in particular?”

“Documentary about aliens,” O says, and he laughs, still looking sheepish. “Guilty pleasure of mine and Yaz’s. Seen this one a million times, but it’s good background noise when I want to wind down.”

“There was a really good one made in the year five thousand,” the Doctor says, enthused, and she takes her sonic out to fiddle with the remote. “Let me see what I can…” She pauses, catching the look O is giving her. “Am I being awkward?”

“Not at all,” O says to her, and the expression on his face is so _soft_ that it makes her want to hide in a hole. “It’s just… it’s good to see you. Missed you.” He rests a hand on her shoulder, gives it a squeeze, then hastily lets it go, clears his throat.

Whatever has been building… dissipates. Or maybe just goes and hides.

“So dinner,” the Doctor says, her voice a little too bright, “what were you thinking?”

“Yaz had a hankering for Chinese, asked for some leftovers,” O says, a little too loud. It doesn’t break the tension. “Sound good?”

“Excellent!”

-*-

“Can I ask a question?” Some hours later, there’s been some wine (“Yaz isn’t a big fan of it, but it’s nice to have an excuse to enjoy it with someone else who likes it, right?”), and the two of them have a horrible B movie on in the background. The alien documentary ended ages ago, and there’s a sucking, empty silence nibbling on the edges of the movie sounds. 

“I dunno if you’ve ever refrained from asking a question,” O says, and he’s barely even slurring. He looks sleepy, his eyes half lidded, and his hair is tousled. He laughs more when he’s a little tipsy, and maybe she’s imagining things, but his eyes seem to linger on her lips, her collarbones, the curve of her profile. 

“I mean,” says the Doctor, “I can be tactful. Sometimes.” 

He raises an eyebrow, takes a sip of his wine, and she mirrors him, takes a sip of her own. 

“I can be,” she insists. “I’m a prime diplomat!”

“I’m sure you are,” he says, and his tone is teasing. “But what was your question?”

“How’d you end up in Sheffield?” She swirls the wine in her glass, takes another sip, then a bigger one. He’s still looking at her, and all she can think of is the way the stars in the Outback looked reflected in his eyes, all that time ago. However long it _actually_ has been. 

“Well,” says O, and he sighs, “after…” He makes an expansive hand gesture, no doubt referencing the business with the spies and the rest of it, “I felt a bit spooked about being alone. I stayed with Ryan and Graham for a while, since… they knew what it was like.” He looks sheepish, takes a drink and looks at her over the rim of the glass. "Is that weird? After all the theatrics, and the business with the plane, I just wanted to talk to someone who understood. And they did. And then Yaz was coming by, naturally, and…” He clears his throat, looking bashful. 

She nods, although she’s not sure what to say about that. 

“So… I like it here.” He clears his throat. “I can work from home, mostly, since I’m an analyst.” His expression goes slightly rueful. “I think living in the Outback was making me weird,” he adds. “Humans get squirrely when they're on their own all the time. The secret service folks are nice enough, but…" He gives a shrug. "Figured I could do with a change of scenery," he finishes. 

"And then you wanted to move closer to Yaz?" More wine swirling. Why is she poking this? It's like prodding a sore tooth with her tongue, and she needs to stop. She needs to _go_. before she does something… ill advised. She isn't even sure what she's so anxious about, truthfully. Some kind of tension is mounting, and she can't seem to stop poking it. 

"Well," he says, and he clears his throat. "Well. We didn't originally… plan it." He gives an awkward laugh, and he's talking faster, as if spurred on by the alcohol. "We fell into bed together a few nights after you disappeared, and it kept happening, and then…" He shrugs, then covers his mouth with one hand. "Shouldn't have said that," he adds. "Sorry. Wine is getting to my head." 

There's an awkward silence. 

“Did you tell Yaz?” She blurts out before she can stop herself. “About what happened between us in the outback.”

“Uh…” Oliver avoids her eyes while he pours out a drink for her. “I… didn’t think it was appropriate,” he mumbles, and his cheeks are tinged pink. “I mean you were kind of… a sore topic. I thought bringing up what happened between us might only make that worse.”

“Oh,” she replies. “ _Oh_. Right, yeah.” Feeling that bubble of guilt that’s starting to become familiar inside her chest again, she takes another sip of her wine.

"I missed you," O says, and he's staring pensively down into his wine. "We both did. I think Yaz felt it more strongly than I did, like she said. I'm more used to your more unreliable tendencies." Then he makes a face, no doubt catching the look on her face. "Fuck. Wait, no, sorry." He covers his mouth with one hand. 

"Are you apologising for the swearing or for saying I'm unreliable?" The Doctor tried not to sound offended. That had stung. 

"Both, I suppose," he says, and he looks sheepish. "Making a right cock up of this, aren't I?" 

"A bit, yeah," the Doctor says, but she's grinning in spite of herself. She's always felt comfortable with O. She can't help it. 

“I’ll be right back.” He gets up, making his way towards the toilet, and when the door closes the Doctor takes a deep breath. 

_I should probably go,_ she thinks, staring into the purple depths of her wine. _I’m just tired and discombobulated. Need to get away, come back when it’s the both of them and we can go on a proper adventure._

She’ll get up. Any second now, she’ll get up. 

-*-

When O returns, he steps over the Doctor’s legs to reach his place next to her on the sofa, only his foot catches on her shin, and he trips, gives a sound of surprise, and in the next second he is sprawled out on top of her and staring down into her eyes with his wide ones.

“Shit. Sorry Doctor, I uh… maybe shouldn’t have had that second glass,” he gives a chuckle.

“It’s okay,” she says. Or, at least that’s what she _means_ to say, only that’s not what leaves her lips. Instead she emits a squeak as another pair of lips press clumsily to her own.

“Sorry,” O pants out with a puff of air against her mouth when he pulls hastily back before she scarcely registers he’s kissed her in the first place. He’s still staring at her lips, and the Doctor licks them subconsciously, taking a breath of air that seems to push her chest closer to his. Her nipples tingle, and her own eyes flicker down to his mouth.

“No need to apologise,” she manages, scarcely above a whisper. 

He kisses her again, and his stubble is rough against her cheeks, her palms as they cradle his face. His tongue is gentle against hers, and then his fingers are in her hair. 

_Does he kiss Yaz like this?_ She sighs, and somehow she's straddling his lap. He's hard against her thigh, and his hot breath is gusting across her face, smelling like their dinner and the wine. 

They shouldn't be doing this. It would break Yaz's heart, to know that the Doctor is taking something else from her life, but O was the Doctor's first (only a couple of weeks ago, for her), and she can’t seem to find it within herself to push him away. 

Which isn't fair, but it's hard to be fair when there are warm hands kneading her breasts through her t-shirts and stubbly kisses moving down her neck. 

He was the last one to touch her like this, and it's exactly what she needs. 

He is hard against the seam of her trousers when she bears down against him, and she wonders if that had happened in the thirty seconds they’d been kissing or before that. Unable to help herself, she grinds her hips down against him, breaking from the kiss to gasp against his open mouth as the bulge in his trousers rubs against her in all the right places.

One of his hands glides up to the back of her neck, and grips her there, the other fumbling to slip up under her shirts so he can palm a bare breast. Their breathing is laboured and loud in the quiet of the flat, and the Doctor feels herself grow wet and hot between her legs, swears she can hear it as she grinds against him.

He fumbles down her braces, and she's pulling his shirt up and over his head. His dark chest hair is soft against her palms as she runs them over it, and he hisses through his teeth when she tugs on it..

"Remembered, eh?" He smiles at her, his eyes faintly glazed, and then he's shoving her t-shirts up and off, leaving her topless. 

His mouth is _hot_ on her nipple, and he only pulls off of her when she digs her fingers into his shoulders. 

"Be careful about leaving marks," he says, making eye contact. "I bruise like a banana, and, um…" He trails off, but he's still holding eye contact. His lips wrap around her nipple, sucking it into the hot, wet cavern of his mouth, and she stifles a moan, the same way she did back in the Outback. 

Humans are so _warm_ , a scalding heat that seems to worm its way inside of her and settle in the depths of her guts, fueling the desperate arousal that's already growing inside of her. 

She can’t think about what she’s doing. Because if she _thinks_ that means she has to acknowledge that it’s wrong, and if she does that she is going to have to stop, and the Doctor doesn’t want to stop. 

So, instead of thinking she presses her lips to O’s again, kissing him hard, pushing her tongue into his mouth as she fumbles between them for the fastenings on his trousers.

The button gives way to her shaking fingers, and she stands just briefly enough to divest herself of her own trousers and underwear so that when she sits back down in his lap she can slide her cunt over the bare hot length of him.

They both groan, and the Doctor braces a hand on O’s shoulder, still refusing to think as she breaks the kiss to glance down between them.

It’s rushed, and fumbling, but in the next breath she has the tip of him inside her, and she’s lowering her hips to take him in, gasping at the feel of him sinking into her and stretching her out.

 _Has he been inside Yaz today?_ She wonders, then immediately kicks herself for doing so, remembering that she was definitely _not_ thinking about that. His eyes are dark when they lock with his own and his full lips are parted, his fingers flexing on her bare hip.  
_I wonder if he’s showered since…_

He’s groaning in her ear, as she sinks down on him. He’s solid, and she clenches around it, her eyes squeezed shut. When she’s fully seated, he flexes, and his thumb comes between them. His thumb is on her clit, and she shudders around him and kisses him.

There’s the same wet sounds from when she was watching the two of them, and she whimpers into the kiss. _Does he kiss Yaz differently from how he kisses me? Or is it the same technique?_

He’s still rubbing her clit, and then he’s kissing lower, to mouth at her breast. Her nipple is in his mouth again, and his cock seems to be hitting her g-spot - _how is it hitting so perfectly, how is he managing to make it so good?_ \- and she’s clenching around him already, letting go of his shoulders to grab at the couch behind him. 

“Doctor,” he moans, and he’s pressing his face into her breasts again, the roughness on his cheeks abrading the delicate skin of her sternum. She can’t stop shaking, she can’t breathe, but then he does _something_ , and his cock flexes inside of her and his teeth dig into her nipple, and the orgasm is pulled out of her, leaving her limp and floppy against him as he humps into her. 

“You’re so tight,” he gasps into her ear, just like he did that first night, and his hands are digging into her hips, jerking up into her. _If Yaz walked in on us, she’d see it like I did_ , the Doctor thinks, and that sends another desperate, hot wave through her, as she clenches around him, and then she whines as he pulls out of her. 

His cock trembles and jerks, come spurting across her belly in a sticky, warm splatter. He flops back against the couch, and his chest is heaving, sticky with sweat. “Fuck,” he says, his voice thick. “Oh my god, I haven’t... “ 

“Good, then?” The Doctor tries not to sound offended at how it had ended. She’s still trembling with arousal, her knees weak and her thighs sore from being held open by his sides. 

“Pretty good,” he agrees, and he has the audacity to _wink_ at her, the bastard. “Different from the last time.” 

She flushes, remembers the tenderness the last time they fucked. The gentle way he had touched her face, the feel of him moving in and out of her as she stared up at the great sky full of stars overhead. 

“I… realized, after the fact, that I wasn’t sure if I’d be able to get you pregnant,” O says, and he looks sheepish now. His thumbs are rubbing little circles on her hips, “I usually come inside Yaz, since she -”

“Has an IUD, yeah, she told me,” the Doctor interrupts. 

“How’d that come up?” O’s eyebrow goes up.

“It… came up,” the Doctor says, clears her throat. “Wanted to make sure you… wouldn’t possibly get pregnant while on the TARDIS, since… y’know.” 

“Hm?” He looks at her, the picture of human inquisitiveness. 

“Children conceived on the TARDIS go… strange,” the Doctor says. _And it would be too weird to possibly end up marrying this one_ , she doesn’t say, but thinking about marrying makes her think of the ring on Yaz’s finger, and that makes her stomach twist up unpleasantly. 

“I see,” says O.

She shakes her head to rid it of thoughts of her, and gives him a breezy smile. “No worries about that with me. We’re not compatible - biologically speaking.”

“Oh right,” O nods. “Good then. And sorry I suppose,” he adds a little sheepishly, eyes flickering down to where his come is splattered across her belly. “I can… make it up to you, if you’d like?” He smiles at her, shy and through his eyelashes, and her cunt clenches around nothing. 

“If you’re sure,” the Doctor says, but she’s already letting him maneuver her back onto the couch, and then he’s crouching between her legs. 

“Yaz isn’t due home for a while yet,” he says, his hands going to spread her thighs open wider. He mouths at the softness of her belly, licking up his own come, and she shivers at the wet, slippery feel of his tongue. There’s a faint film of his come and his spit across her belly - _does he do this for Yaz, too?_

The Doctor closes her eyes, and she imagines his dark hair against Yaz’s thighs, her belly. It turns into her _own_ blonde head between Yaz’s thighs, and she lets her legs spread wider, as his hot breath gusts over her pubic hair. It’s ticklish, and his tongue is scalding hot as it worms between her labia, as it passes over her clit.

The Doctor sinks her fingers into O’s soft, dry hair, and she gasps as his lips fasten around her clit, his tongue wiggling over the tip of it. She rolls her hips and tries to concentrate on the act itself, tracking the movement of his tongue, every flick of that clever little muscle. 

He takes her whole vulva into his mouth and sucks, then worms his tongue between her labia, pressing inside of her, and _that_ is an interesting sensation that she wants to examine, but then he’s pulling back to suck on her clit again, rolling his tongue over it in pulses, and there are embarrassing noises filing the air, grunts and gasps. They must be coming out of her mouth, because she can feel her vocal cords vibrating, but that _can’t_ be her, she’d know, right?

She doesn’t remember it being so _wet_ \- fluid dripping down her perineum, down his chin, smearing over her thighs. She was so _sticky_ , and he kept making more wet noises. Had it been like this, from the other end? 

He wiggles a hand beneath his chin, and the Doctor gasps as he presses two fingers into her. They slide in with ease, more of that wetness seeping out and _god_ she was going to ruin their nice sofa and what would Yaz think, if she saw the stains tomorrow? If she came home tonight and sat down on a wet patch? 

O does something with his fingers inside her that banishes that train of thought rather quickly, until all she can focus on is the duel sensations of the stroking motion his fingers are making inside her, curled up towards his mouth, and the hot clever tongue flicking rapidly over her clit.

Her thighs shoot up and press together as she comes, his head clamped between them, toes curled and heels digging into his shoulder blades as she shudders and gasps, more of those desperate keening sounds filling the room. When he lets up and she slumps down, blinking a little dazedly at him as he rises from between her legs, they are both panting hard, and she knows her face must be as flushed as O’s. 

“Well,” he says, wiping his glistening mouth on the back of his hand. Her face flushes further. “Felt like that took care of it.” There’s a cocky glint to his eyes that’s not quite like him, but the Doctor finds it only makes heat swell inside of her as she gazes back at him through the post-climatic fog of pleasure.

“Yeah,” she pants. “That was…”

“Amazing,” he fills in for her with a contented groan as he crawls up to collapse next to her on the sofa, wedged in against the back half on top of her. 

It was funny… it felt like O should be panicking about now. That’s usually what people did after they realised they’d done something awful wasn’t it? And this… this was _awful._ O was engaged… to Yaz. Amazing, wonderful Yaz who the Doctor adored, and if she found out what had happened between them tonight she would be heartbroken. 

Chest hurting suddenly, the Doctor pushes at him, scrambling out from between him and the sofa and yanking her clothes together.

“This was… this shouldn’t have happened,” she says with a lump in her throat. O sits up behind her as she pulls her clothes together.

“No, it shouldn’t have,” he agrees quietly, and sounds more sober than he had a minute ago. He grabs her hand as she bends to pick up her shirts, and she turns to look at him. His dark eyes are wide and worried. “You’re not going to tell Yaz, are you?”

She frowns, shaking her head. “No - it would hurt her.”

O nods. “Yes - I mean - I know it would be the right thing but… yes, you’re right, it would hurt her. I don’t want to do that. I never did.”

“Me either,” she says quickly. “This was just… a mistake. - Because of what happened between us before. Won’t happen again.”

“No of course not,” he shakes his head very seriously with a frown and they stare at each other a moment. O’s eyes slip downwards, sweeping over her hastily half-dressed rumpled form, and she quickly yanks her hand from his to throw her shirts over her head, shoving them into her trousers.

“I should go.”

“Yes,” O agrees. He’s grabbing his own shirt now, and throwing it on as the Doctor shoves her feet in her boots, almost stumbling in her haste to make for the door.

“See you tomorrow yeah? Pick you both up around lunch?” She calls out as she practically bolts for the door, grabbing her coat.

“Yeah, sounds good.”

“Tell Yaz I said -“ she cuts herself off before the ‘hi’... didn’t really feel appropriate somehow, after what her and O had done, when his come was still drying on her belly...

They lock eyes, equally wide for a suspended second, before she whirls on her heel and yanks the door open.

“Bye!” She says quickly before hastening out, slamming it behind her and marching quickly back in the direction of the TARDIS.

 _Doctor,_ she berates herself as she walks, still pleasantly hot and uncomfortably damp between shaky legs. _What have you done?_

-*-

Back inside the flat, the Master pours himself another glass of wine, boxers and shirt on but still open, and reclines back on the sofa, propping his feet on the coffee table as he takes a sip. Usually he doesn’t much like wine, but this particular brand isn’t too awful - and he thinks he’s earned it tonight.

The Doctor is playing right into his hands and this is all playing out _so much better_ than he ever could have imagined.

-*-


	4. Chapter 4

**Notes for the Chapter:**

> So for a warning, this is gonna get mean. The Master ain't exactly a nice guy, but... it gets _mean_.
> 
> Also, the Master's human name has changed from Omar to Oliver. Apologies for any confusion!

Yaz is leaning against her squad car at the top of a car park when she hears the familiar wheezing groan of the TARDIS. She hates the way her heart jumps into her throat at the sound, hates the way she spins around to find it.

The TARDIS materializes behind her, as familiar as her own face, and she hates the ache that’s already setting up in the pit of her stomach. Her heart leaps up when the Doctor steps out, and she’s smiling in spite of herself.

“Yaz,” the Doctor says, and there’s an anxious expression on her face. “How are ya?”

“I’m doing well,” Yaz says, and she glances over the Doctor’s shoulder, into the golden light of the TARDIS. “Is Oliver with ya?”

“Nope,” says the Doctor, and there’s a split second of… something on her face, something that Yaz can’t entirely understand. “Thought I’d check in on my favorite PC!”

"I can't be your favorite PC," Yaz says, and her tone is mostly joking. "You've got another stashed away, surely."

"Nope," the Doctor says. "You're _definitely_ my favorite." She comes to stand next to Yaz, as the two of them look over the city in front of them, the wind blowing chilly across the open roof of the car park. "What're you up to, Yaz?"

"Oh, y'know," Yaz says, and she shrugs, looks at her feet, looks back at the Doctor. "End of the shift. Figured I'd have a bit of quiet time is all." She shrugs. "Not exactly busy, 'round now."

It's half past midnight, and the chunk of the city that she's been assigned to is always quiet at this time. There are barely any stars in the sky, with all the light pollution, but the moon is wide and full overhead. 

The Doctor leans against the squad car, and when Yaz glances over at her, she sees that the Doctor is looking at her intently, eyebrows drawn together, a deep line etched into her forehead. Yaz wants to smooth it out with her thumb, wants to feel the Doctor's skin against her own. 

"D'you think I'm a good man, Yaz?" The Doctor asks, and then she frowns. "Wait, no. Woman. D'you think I'm a good woman?" Another pause. "That don't sound right either. Good person?"

Yaz opens her mouth, glances over at the Doctor. She closes her mouth, stares down at her hands, at the city underneath them. She hooks her thumbs into the belt loops of her trousers and leans a little more heavily against the car, the metal cool against her back even through all the layers. 

"Goodness isn't just a thing you _are_ ," the Doctor continues, as if she's speaking from a long way off. "It's a thing you _do_ , and I know it's... hard sometimes, to do the right thing. It's easier to do the wrong thing." 

Yaz nods, although it seems a bit like the Doctor is just talking to talk. _Does she even need me around, specifically, or just a listening pair of ears?_ The thought is surprisingly cruel, and Yaz is faintly shocked at herself. 

"I trust you to do the right thing," Yaz says instead, because... what if she says the wrong thing? What if she says the wrong thing and it scares the Doctor off, and then she never sees this wonderous mad alien again? 

"It means a lot to me," the Doctor says, and the look she's shooting Yaz is so full of intense sincerity that it's making Yaz faintly queasy. "That you think so much of me. Because you're such a _good_ person, Yaz, and you do so many good things, and I know..." She trails off, and she's pacing now. "I know that if you're a good person who believes in me, I must have _some_ good person in me, right?" 

_Oh no, she's spiraling_ , Yaz thinks. "I missed you," she says, although she isn't sure if that's the right thing to say. What do you say, at a time like this?

The Doctor stops pacing, and then she's moving closer, so that she's looking straight into Yaz's face. They're so close that their noses are almost touching, and Yaz can smell... something familiar. She can't quite put her finger on it - maybe it's the Doctor's scent itself? 

"Yaz," the Doctor said, "I was in... a bad place. For a _very_ long time." The manic look is returning to the back of her eyes, and in the yellow light cast from the nearby lamp, it's making Yaz's stomach twist up. There's something in there that she could drown in, if she isn't careful.

"I'm sorry," Yaz says, because she's not sure what else to say.

"I've done a lot of bad things, Yaz," the Doctor says, and she looks so _sad_. "Bad things, things that you can't even begin to comprehend. If you even -"

Yaz kisses the Doctor.

She shouldn't have done it. She should have taken a step back, maybe taking the Doctor's hand and squeezed her fingers - no, wait, that would be too intimate too, wouldn't it? But the Doctor had been looking at her with those limpid, hazel eyes, red rimmed and sad, and all of that yearning seems to be coming out with the pressure of her lips and the way she clutches at the Doctor's coat.

Yaz pulls back, and her heart is beating desperately in her ears, her chest rising and falling rapidly. The Doctor's lips are soft, and the Doctor's hands are cradling her face, thumbs on her cheekbones. When they pull apart, the Doctor is trembling, but then _she's_ kissing Yaz, pressing so close that they're belly to belly, breast to breast. Yaz's radio is probably biting into the Doctor's chest, and one of the Doctor's hands is on the back of Yaz's neck now, pressing down. Her fingers are very cold.

They break apart, both gasping like they've been drowning, and the Doctor's nose is cold against Yaz's cheek. "I shouldn't do this," the Doctor whispers, but she's kissing Yaz again, fumbling at the front of the bright yellow vest, and then the Doctor is met with Yaz's coat. Her tongue is in Yaz's mouth, and her hair is ticklish against Yaz's face. 

Yaz breaks the kiss this time, and her own hands are moving under the Doctor's coat, sliding under the braces. The Doctor's breasts are firm and warm against her palms, and she squeezes, savoring the sensation. They're as lovely as she's imagined, and she finds the Doctor's nipples under the layers, pressing her thumbs into them. She likes the little hiss of breath the Doctor gives, and the way the other woman shakes against her.

"I shouldn't do this," the Doctor whispers again, but she kisses Yaz like it's the end of the world, and now one hand is on the back of Yaz's skull, curving around it. She's fumbling the button of Yaz's trousers open, and she's pressing Yaz against the side of the squad car, her mouth desperate, needy. Her tongue is in Yaz's mouth, her teeth are in Yaz's lip, and she's gripping the back of Yaz's neck so hard that it may bruise.

Yaz hisses, when the Doctor gets tired of fiddling with buttons and just shoves her hand in, straight into Yaz's knickers. The tips of her fingers ruffle Yaz's pubic hair, and her index finger finds Yaz's clit, already standing at attention. 

"You're already wet," the Doctor murmurs, right up against Yaz's lips. "How are you so perfect, Yaz? You're such a wonder, I can't ever get enough of you, you're..." She trails off, and her mouth is hot and soft against Yaz's pulse point.

_She'll leave a mark, she can't leave a mark,_ Yaz thinks, and then she stops thinking, because the Doctor's sinking a finger inside of her and there's a thumb on her clit, and Yaz sags back against the squad car and rolls her hips to match the movement of the Doctor's arm, thrusting into her rapidly, desperately. 

"Doctor," Yaz groans, and the Doctor presses her forehead to Yaz's temple. The Doctor's skin is warm to the touch, warmer than usual, and they're both sweaty, Yaz trembling, trying to open her legs wider. "Doctor, please..."

"D'you know how much I've thought about this?" The Doctor's voice is getting breathless, as she rocks her wrist, pressing her thumb into Yaz's clit, and there's another finger inside of Yaz, buried up to the last knuckle. They're pressing down on something inside of her that makes her whole body clench like a fist, and she gasps. She can't be too loud, what if someone hears them? 

_There might be a CCTV watching us, what am I going to do?_ Yaz's logical brain was gabbling at her, trying to get her attention, but she didn't _care_ , because there was something building at the base of her gut, and the Doctor's mouth was so hot, the Doctor's fingers were so solid inside of her, filling her so well. 

"Good girl, good girl," the Doctor croons. "Yaz, c'mon, I know you can do it, Yaz, please, you're so amazing, I missed you so much, I'm so _sorry_ …" She sounds so heartbroken, and it makes Yaz's stomach twist up. 

_What did she mean, that she was someplace bad?_ Yaz rides the Doctor's fingers, and she clings to the Doctor’s coat. Their foreheads are pressed together, and they’re breathing each other’s breath. She’s doesn’t think she’s ever had sex like this before, although bits of it remind her of the first time she and Oliver got together, madly rutitng against each other in his little house in the outback. 

“Yaz, you’re the best human I know,” the Doctor says, and Yaz is pretty sure that’s a lie, but she lets her believe it, just for an instance. She throws her head back, as the collecting heat in the depths of her guts finally snaps, and there’s a sensation of something _pushing_ , something wet. Her muscles flutter and pulse around the Doctor’s fingers, and there’s a rush of warm wetness, fluid dripping down between the Doctor’s fingers. She’s soaking into her knickers, her trousers, and she blinks, trying to make sense of it. 

“I don’t usually do that,” Yaz says, and that feels like a crude thing to say. _I just cheated on my fiance with the woman I’ve been in love with for more than a year, and I’m commenting on the fact that I… squirted, is that what I did? How crude._

“First time, eh?” The Doctor withdraws her fingers, and absently licks them clean. It’s the same way she licks her fingers off after she’s been eating sweets, and another desperate pulse goes through Yaz. “I’ve always been good at that.” 

She looks… smug, and then she looks guilty. She takes Yaz face in her hands and they’re kissing again, until the Doctor pulls away to rub her nose against Yaz’s. “I’m keepin’ my phone on,” she says. “You can text me the next time he’s out, I can come pick you up. Or the three of us can go on another adventure. I owe you another adventure.” She nuzzles into Yaz’s temple, presses a damp kiss, and then she’s off in the TARDIS again. “I’ll call you,” she tosses over her shoulder, and then the TARDIS is disappearing. 

Yaz stands there, her trousers damp and open and she covers her mouth to keep from sobbing out loud. What has she _done_? 

-*-

He knows as soon as Yaz walks in.

He can smell the Doctor all over her, the stink of human pheromones mixed in with the deeper, more fleeting scent of an aroused Time Lord. Her stride is different, as if she’s just had an orgasm, and she seems to be walking gingerly, as if she’s… chafed?

“You stayed up for me,” Yaz says, and her expression is guilty.

How does she ever expect to be a proper copper, if she can’t even lie? 

“I always worry when you’re up late,” the Master lies, and he smiles at her, patting the couch next to him. “Fancy some dinner? There’s Chinese in the fridge, we can have a cuddle, watch that stupid alien documentary. There’s a new season.” 

She makes a big show of yawning, rubbing her eyes. “I’m beat,” she says, and she leans down to give him a perfunctory kiss on the top of the head. 

He can smell the Doctor’s spit on her cheeks, along her neck. The other Time Lord must have gone to town on the human, and the Master hides his smirk by nuzzling into Yaz’s neck, kissing some of the spots the Doctor did. 

_Will it grate her, to know that I got my hands and my mouth and my cock on her pet human before she did?_ The Master looks up at Yaz, keeping his eyes limpid and sweet, and he wonders if she’ll tell him about her little dalliance. 

“I’m gonna have a shower,” Yaz says instead, and she kisses the top of his head again, avoiding his eyes. “I’ll come eat after.”

“I’ll heat it up for you, love,” the Master says, settling back on the couch and stretching his legs out in front of him, getting comfortable. 

-*-

When he hears the water turn on, the Master makes his way towards the clothing hamper. He finds her knickers, sticky and cold with arousal, and he smiles, all teeth. _Doctor, you sly dog._ Must have been quite a time, for Yaz to be that embarrassed. 

He sheds his own clothes, making his way towards the bathroom. Time to make things a little more entertaining. 

-*-

Yaz jumps when his hand rests on her hip, and she looks over her shoulder at him, frowning. “Oliver?”

“I thought you might like some company,” he says, and he wraps his arms around her middle. “I missed you, while you were out.”

He likes the way her expression gets sad, and guilt flares like a match. It’s like a shot of whiskey, warming him down to his toes. He smiles, kissing the back of her neck, her breasts in his hands. 

“You’re in a mood,” she says, leaning back against him, and her head lolls back onto his shoulder. His erection is nudging her against her backside, but she doesn’t seem to notice. She must be _that_ caught up in her guilty spiral. 

Time to give her a little nudge. 

“I’ve got the most beautiful woman in Sheffield, right here,” he murmurs, and he kisses along her neck. He finds the spots the Doctor probably went for (where the Doctor used to go for on him, When he still wore corsets and skirts), and he lips and nibbles on them. He rolls her nipples between his thumb and fingers, and she shudders against him, more bursts of arousal mixing in with the guilt. 

“You flatterer, you,” she murmurs, and then she sighs, as his hands move lower, to stroke her between the legs. He finds her clit, rubs the sweet little nerve under his index finger, and she goes stiff against him, panting shallowly.

‘“I just love you so much,” he says, and another flare of jealousy. “I know I could trust you with anything. After everything that happened…” He trails off, and his hands move lower, to probe at her entrance. She’s slick and wet - _what did you do, Doctor, to get her this worked up? I may need to up my game._

She’s trembling against him, as he rubs her clit in slow, quick circles. She shudders when he gets on his knees, and then he’s licking her from behind, hands on her hips to keep them jutted out. His neck is at an awkward angle, but he can taste traces of the Doctor as he licks her, his finger rubbing her clit in more little circles, and she’s planted her feet.

He probes her mind, and tries to find some nibble of whatever it was that the Doctor did to her. But it’s all a whirlwind of guilt, and he lets himself get lost in licking, sucking, pulling the beginnings of her orgasm out of her. He keeps at it with his fingers, and he moves to kiss and mouth at her backside, nipping a cheek, then spreads her open.

“Oliver?” Yaz tenses against him, and she looks over her shoulder. 

He doesn’t say anything, just mouths at the cheek of her arse, moving further in. The flat of his tongue swipes over her asshole, and she jerks away.

“Oliver,” she says, sharper this time. 

“Sorry,” he says, not meaning it. He stands up, hissing at the pain in his knees, and he presses a little closer to her. The head of his cock presses against the cleft of her arse, and then he pushes it lower, nudges it at her cunt. “Can I make it up to you, love?”

She spreads her legs a little wider, but doesn’t say anything else. She leans into the wall, and she sighs as his cock slides into her in one smooth, long stroke.

“You’re so warm,” he murmurs into her ear. It’s one of the things about humans that always gets to him. So hot, the single heartbeat thudding around him. He fucks her quick and fast, and he keeps his thumb on her clit. He likes the way she sobs as she comes around him, and the quiet, guilty hiccup at his _I love you_ makes him come inside her, so hard he sees spots before his eyes. 

-*-

Inside the console room, the Doctor paces round her console, heels of her hands pressed into her eyes. 

She shouldn’t have done that. She _knows_ she shouldn’t have done that - with either of them - what had she been thinking!?

O is just… open and wonderful, and there’d been so many years of friendship and easy flirtation that culminated in that night in the outback - just the other week for her - and he had felt so _good_ it’s impossible to resist another taste. It was like… he knew her. Like somehow he just knew how to touch her and hold her, and when he looked into her eyes there was something achingly familiar in their depths. She supposed it was just how long she had known him - from her point of view. Back before she was even this her. O probably knows her the best of all of her current friends, and that makes it so easy with him - a familiarity that just feels safe. 

And Yaz…

She isn’t blind, the Doctor knows that Yaz adores her. She looks at the Doctor like the most special ones always did - like she’d hung the very moon in the sky, and for a being as ancient as the Doctor that kind of adoration is intoxicating. And she means what she’d said to her… Yaz is so _good._ So inherently good and kind and just, and being loved by someone like that is something the Doctor desperately needed. 

And it is just all mixed up in the strange hollowness it has drilled inside her to learn the two of them are together. She is happy for them - she’d never begrudge the ones she loved of happiness, but at the same time the revelation has left her flailing, scrambling to feel like she needs to hold on tight to the two people whose presence in her life had felt like a certainty just the other week, and now it is like they are slipping through her very fingers. 

Sleeping with O is bad enough, what a whole, horrible mess she has produced now that she’s fallen into Yaz too. She never would have done it - but Yaz had looked at her with those big dark eyes so vulnerable and aching in the moonlight, and all the Doctor wanted to do was make her feel _good._ Rejecting her then would have broken her… she doesn’t want to think on how much worse not doing so had the potential to be. 

She just needs to talk to her. She’d been quite clear with O after the fact - she should have the same conversation with Yaz. They were getting married - and the Doctor knows that the two humans would be able to find so much more happiness with each other than with her. 

Giving a sigh, she turns and braces herself on her console, head bowed. The TARDIS hums softly beneath her touch, and she knows the gentle whirr is berating as much as it is comforting. 

“I know,” she mutters. “I messed up - I _know.”_

Another whirr. 

“I’ll fix it. Take them both someplace fun tomorrow and then I’ll talk with Yaz after.”

Silence. 

“I will! It was… a slip in judgement. It’s been a weird few days,” she mumbles, fiddling with a lever, and then frowns, lifting her head to glare up at the time rotor. “And it’s your fault anyway! I aimed for a week after I last saw them - you’re the one who dumped me here eighteen months too late!”

The ship makes another noise, louder this time, an irritated edge to it. She huffs, spinning to lean back against the edge of the console instead, arms folded. She chews on her lip, looking down at the floor. 

“Maybe you were trying to keep me from them anyway, huh?” She mumbles, quieter to no reply. “You’ve seen how it ends when I get attached to humans… always the same.” Another sigh, and she reaches out behind her to place a hand on the console again. It’s warm beneath her touch, and she knows she won’t be able to stay mad at her ship - she never can. 

“I’ll fix this,” she says again, firmer this time, and gives the console a pat before pushing herself upright, forcing a smile. “You’ll see.”


	5. Chapter 5

“Have you two figured out what you’re gonna do for your honeymoon?” The Doctor leans on the TARDIS console. There’s something manic in the way she’s moving, and it’s making Yaz edgy. She can’t seem to take her eyes off of the Doctor’s hands as they gesture madly, remembering the feel of the Doctor’s fingers inside of her.

“Not really, no,” Oliver admits. He’s got an arm around Yaz’s shoulder, and his thumb is passing over her, gently. She remembers _his_ fingers - she had his fingers in her hair this morning, kissing her in their bed in the TARDIS. 

“We were thinkin’ of going to Spain,” Yaz adds, “or maybe Bermuda. Someplace sunny, where we could go to the beach.”

“A little done with Australia, though,” O adds. He kisses her temple, and she shivers. _Has he always been this affectionate in front of the Doctor and I feel guilty, or has he gotten more touchy-feely?_ He’s been more cuddly in general lately. Maybe it was seeing all the majesty of the universe or something like that.

She wishes she’d never kissed the Doctor. She wishes she’d never gotten engaged to O. She wishes… she doesn’t know what she wishes, but her stomach is a twisted bag of worry, and she leans into him uneasily, but lets him rub her arm. 

“How about some place a little more exotic than that?” The Doctor does a little twirl around the console, as if she’s dancing. “Honeymoon planet? But not a honeymooning planet, those get too lovey-dovey.” She wrinkles her nose.

“It’s not our honeymoon for a while yet,” Yaz says, “We need to get married first.”

"We can do that too, if you'd like. Wanna get it done quickly." The Doctor rubs her hands together, and there's more of that frenetic energy.

"Najia would kill both of us if we got married, with all the planning she and Hakim have been doing," O says, and he gives her a final squeeze. "Take us somewhere interesting, Doctor," he tells her, and then he yawns. "All that running, though. Wore me out. I'm gonna have a nap." 

"You want some company?" Yaz asks, although she doesn't really want to go with him. The idea of lying with him in the dark, guilt boiling away in her guts... well, it doesn't sound appealing.

"Nah," says Oliver, and he grins at her, cheeky. "I'm planning to starfish, and take up all the covers."

She smiles at him, and gives him a peck on the mouth. "You have a good nap," she tells him, and then he's off down the corridor. 

Leaving Yaz and the Doctor alone. 

For the first time since... well, since that time by the patrol car.

"Doctor," Yaz says, and she takes a step forward. 

"Is your mother that excited for the wedding?" The Doctor's eyes are on the console, as she flips switches and pulls levers. They don't seem to be doing much of anything, since the TARDIS isn't shaking or shuddering, just humming quietly. 

"Doctor," Yaz says again, a little more insistently this time.

"Mothers tend to love weddings," the Doctor says, and she shoots a glance up at Yaz. There's what looks like blind panic in the back of her eyes, and Yaz's own heart is in her throat now. "I know it's a little unorthodox, but it always helps to kick the tires before you go to a place, y'know?" 

"Doctor." Yaz reaches a hand out, puts it on the Doctor's shoulder. 

The Doctor freezes, and she looks at the hand on her shoulder, then looks into Yaz's face. "Yaz," she says, and her voice is... old. Sad. 

"Are you alright?" Yaz steps closer, so that they're almost nose to nose, and the familiarity of it makes her chest hurt. 

"I shouldn't have..." The Doctor starts, then trails off. 

"I don't regret it," Yaz says, and she's faintly shocked to find she means it. 

"What?" The Doctor stares at her, wide eyed. 

"I don't," Yaz says. "I know I should probably be ashamed or... or guilty, and maybe I'm a little guilty, but I know that you won't be here forever, and I know that in life you need to seize the opportunities you have, especially when I know you'll leave some day and then -"

Yaz doesn't get to finish her sentence, because the Doctor kisses her. The Doctor presses her into the console, and her fingers are tangled in Yaz's hair, her mouth hot and wet against Yaz's own. When they pull apart, the Doctor is staring wide eyed and panting. 

"I shouldn't have done that," the Doctor whispers, but she kisses Yaz again, and her hands are on the hem of Yaz's shirt, pulling it up. She shoves the cups of Yaz's bra down in a desperate, groping motion, and her hands are cool and solid on Yaz's breasts. "Oh, _Yaz_ ," she murmurs, as she kisses down Yaz's neck. 

Yaz hisses, throwing her head back and pushing her chest forward. She plants her feet, and she's already starting to roll her hips, wetness flooding between her legs. How does the Doctor manage to _do_ this to her, every time? 

Every time, as if they've done this more than once before.

... every time, as if she hasn't spent countless nights with a hand between her legs (or her fiance between her legs, come to think of it), thinking about something like this. 

"Oliver... might come back," Yaz says, as her hands go to the Doctor's blond hair, but the Doctor just makes a muffled agreeable noise and bites Yaz's breast, right beside her nipple. 

"Tell me to stop," the Doctor says, and she's looking up at Yaz with wide eyes. They're very dark, and her cheeks are very pink.

Instead of saying anything, Yaz cups the Doctor's cheek. She presses her thumb against the Doctor's lower lip, slipping the very tip of it into the Doctor's mouth, pressing down on the Doctor's tongue. 

The Doctor sighs, opens her mouth a little wider, and she sinks to her knees. Her hands aren't trembling, as she undoes Yaz's belt, but Yaz's are, as she rests her other hand on top of the Doctor's head. 

The first pass of the Doctor's tongue through her thin cotton knickers make Yaz's knees go weak, and she leans heavily against the console. She's going to have _imprints_ on her backside, if she's not careful. 

The Doctor moans, and then she grabs Yaz’s hand, and presses it against her scalp. “Pull my hair,” she says, and her voice is rough. “Please.”

Yaz gives it a tug, and the Doctor moans loudly - loud enough that Yaz is faintly worried Oliver will hear. She can see the glint of her engagement ring, buried in all that blond hair, and she widens her stance and hunches her hips, her eyes squeezing shut. She’s panting, as the Doctor begins to lick, expert little tongue flicks.

She loses herself in the pleasure, and some part of her still can’t comprehend that she’s doing this with _The Doctor_ , that she’s in the TARDIS, the light changing color outside her closed eyes, and the Doctor is licking her pussy, the Doctor’s tongue wriggling inside of her, the Doctor’s lips wrapping around her clit. She pulls the Doctor’s hair and covers her mouth with her other hand to keep from making any noise, but her heart is beating desperately in her ears.

“You’re always so wet for me,” the Doctor murmurs into Yaz’s thigh, and she gives it a gentle little kiss, then her mouth is on Yaz’s vulva again.

_You’ve only done this sort of thing once before_ , Yaz wants to say. _That hardly counts as “always”_. She doesn’t say it, though, because the Doctor’s mouth is on her clit again, and she’s beginning to quake, twisting the Doctor’s hair in her fist as her hips stutter forward. She hears the Doctor give a muffled groan, and when she opens her eyes to look down, she can see the Doctor’s shoulder moving.

It takes a moment for Yaz to take stock - the Doctor is holding on to her hip one handedly, and the other hand is… oh. 

The Doctor’s hips rock forward, meeting her own hand as she licks, rubbing herself with the kind of fervency that Yaz associates with being young and new at all things sexual. Then again, the Doctor would be, wouldn’t she? 

_Has she done much else, with anyone else?_ Although this isn’t the time to think about that, is it? She’s on the very edge of coming, trembling on the precipice, and then she’s making eye contact with the Doctor again, and the Doctor is sucking on her clit, and Yaz has no choice but to come and _come_ , a rush of pleasure that’s almost painful.

The Doctor keeps licking her through it, and then the other woman is sitting back on her heels, the hand down her trousers moving faster, and Yaz doesn’t even realize what she’s doing as she gets down on her haunches. She kisses the Doctor, palms one small breast, and she can taste herself on the Doctor’s mouth, the Doctor’s breath.

“Yaz, please,” the Doctor whimpers, and Yaz isn’t sure what it is the Doctor is asking for. Instead, she pinches the Doctor’s nipple, twists it, and she watches as the Doctor’s hips judder forward and she sobs as she comes, face screwed up. 

The Doctor kisses Yaz, right there on the floor of the TARDIS, and in that exact moment, it’s exactly like all of Yaz’s fantasies, all of her dreams. She holds the Doctor to her, double heartbeat thudding against her chest, and it’s absolutely _perfect_.

-*-

The Master is reading in the library when the Doctor comes in. 

He knows, almost immediately, that she’s fucked Yaz. 

_It really is a good thing that she’s not trying to step out on another Time Lord_ , he thinks, as the Doctor makes her way towards him, her expression full of false cheer that doesn’t at all hide the trepidation that’s clearly nipping at her heels. 

“Didja have a good nap, Oliver?” She stands over him, and he has to school his face not to wrinkle his nose. Oh wow, but those are a lot of human pheromones. Did she fuck Yaz, or roll in the human’s dirty laundry?

“Oh yes, definitely,” says the Master, and he sits up, scooting over a bit to make room on the squashy green sofa. “I’ve always found libraries to be… comforting. Do you think the TARDIS minds me napping in here?”

“I don’t think so, no,” the Doctor says. “She likes people feeling safe in her.” Her expression briefly goes soft around the edges, and the Master has to resist the urge to roll his eyes. She’s always been such a soft idiot about the ship. 

“I’ve always felt safe with her,” the Master says, and he smiles at her through his eyelashes. “With _you_ ,” he adds, which may be buttering things up a little bit too much, but she’s always been susceptible to that sort of thing from her humans. 

Sure enough, he can see her posture relax, and she ends up sitting on the sofa next to him, and when his knee touches hers she doesn’t pull away. He ups the ante by wrapping an arm around her shoulders, and she stiffens, then relaxes against him, just a bit.

“Yaz is off having a swim in the pool,” the Doctor says, which is probably a blatant lie. This close, he can smell Yaz _all over_ her face. She must have given a quick rinse to wash off the worst of it, but it’s very much still there. 

“I’m really glad you two are so close,” the Master says, just to twist the knife. He rubs her shoulder with his thumb, soothing little circles, and she’s still relaxing into him, almost _snuggling_. “She was so hurt when you left. I was worried about you.”

A sigh, and she’s close enough that he can feel her eyelashes as she closes her eyes. “I hope she can forgive me some day,” she murmurs. “For… everything.”

“Yaz is a very forgiving person,” the Master says, which isn’t strictly true, but humans always seem to forgive the Doctor. Much more than she deserves, truth be told. 

And then there’s a warm, wet mouth against his pulse point, tongue darting over his stubble, and he shivers, but he lets her kiss his neck, lets her press her wet cheeks (has she been crying, or is she still damp from washing off from her liaison?) against his own. She kisses him, and he lets himself be kissed, the passive human lover.

“O,” she whispers against his mouth, “what am I doing?”

“What feels right,” he says, and he chases the taste of his fiance on her lips, her tongue. His hands find her breasts, but she’s shying away from him, sinking down to the ground and going between his knees. 

“I want to make you feel good,” she says, and now it’s her turn to look up at him through _her_ eyelashes. 

The sight is enough to make his cock twitch, and he rests his hand on top of her head, catching glimpses of her and Yaz - the feeling of Yaz’s hair in her own hair, the sensation of Yaz against his tongue, ticklish private hair and wet, slippery skin. 

“You do,” the Master promises, threading his fingers through her hair, “but… if you want to do more…” He trails off, but his eyes dart from her mouth to his lap, then to her eyes.

She licks her lips, and her hands are on his inner thighs, rubbing the soft cotton of his lounge pants. She leans back as he pushes his waistband back, and he hisses through his teeth as the cool air hits the hot skin of his erection. 

The Master puts a hand on the back of her head, and he wraps his fist around his erection. He sighs when her mouth - cooler than Yaz’s, but still hot - wraps around the head, her tongue slipping under his foreskin, then pulling out. He’s trembling as she takes more of it into his mouth, and he closes his eyes, remembers the last time they did this.

The Doctor had been wearing a suit with trainers, and he’d had blond hair. The Master has to admit that he misses that slightly hurt, betrayed look, since the hazel eyes staring up at him are damp, but more guilty than anything else.

“You’re good at this,” he tells the Doctor, and he makes himself sound breathless as she bobs her head. He has her hair in his fist now, and he’s so tempted to be rougher with her, so tempted to just shove his cock into her until her respiratory bypass kicks in, but that wouldn’t be the sort of thing that O would do, would it?

O is supposed to lie there and take it, and that rankles more than he thinks it should. 

Then she’s taking him all the way down into her throat, deep enough that she’s gagging, and he can feel the sense memory of her sucking on Yaz’s clit in her mind. _Always with that human_ , he thinks, and he pushes himself a little bit.

She gags around him, a spasm, and she moans. She’s squirming, and her moans vibrate along his shaft as he gives short, shallow thrusts. There’s spit dripping down his groin, over his balls, and she’s kneading his thighs, his hips, her eyes streaming. 

“Fuck,” he pants, and he doesn’t even have to pretend that he’s close, that he’s enjoying it. He’s abruptly almost at the brink, his cock pulsing and twitching in her throat, her mouth. _Should I tell her?_

He looks down at her hallowed out cheeks, her streaming eyes, and he doesn’t have a say int he matter, because he goes off like a goddamn _rocket_ , and he comes down her throat. 

She chokes, gags, but she swallows, and he pulls himself out of her mouth, stickiness against her lips, dripping down her chin. 

“I am _so_ sorry,” the Master says, in his best O voice. “I am _so_ sorry, I shouldn’t have done that, I usually -”

“No,” the Doctor says, sitting back on her heels, and she wipes her mouth on the back of her hand. “No, no, it’s fine. It’s just been a long time since I’ve done that.” Her voice is rough, and his cock would get hard if he hadn’t just come. 

“I usually don’t… y’know, I…” He licks his lips. “I usually, y’know, uh.” He clears his throat. “Yaz can’t take it that deep,” he says, “and she doesn’t, y’know... swallow.”

“Oh,” says the Doctor, and she clears her throat. “Well.” Another throat clearing. “Well. That was…” She stands up, her legs shaking, and he reaches out to her. “I need to, uh… see to the Ionizers. Stabilizers.”

He reaches a hand out to her, one hand on her hip, and she takes a step back. “D’you want me to return the favor?” He likes how rough her voice is, the way her lips are all swollen up.

“No,” she says. “No, no, I’m fine.”

“Are you sure?” He tucks himself back into his trousers, and he just watches her.

“Yes,” she says, “yes, it’s okay. It’s fine. Great.” She gives him a smile, and it’s only a little forced. “Absolutely fine.” And then she’s off, her blue coat flapping behind her. 

The Master smiles in the empty library, and leans back into the couch, his feet propped up. That was unexpected… but things are probably going to get even more exciting, before it blows up. 

He really can’t wait.


	6. Chapter 6

The Doctor is lying on a sun lounger by the pool, her hands behind her head, staring up at the aurora, when Yaz finds her. 

Really, she shouldn't be here in the first place. Should have just dropped the humans off for their pre-honeymoon, then moved forward in time to pick them up. They'd be cheerful, freshly fucked, tired out and sunburnt. 

But O had looked at her beseechingly and said something about her needing to relax a bit, and Yaz had agreed, and now... she's on a honeymoon planet. By herself. The two of them disappear periodically, then come back, and it feels almost like a pitying sort of company. She'd go to find some trouble popping up, but she'd made sure that this was an especially _quiet_ time, so the two of them can enjoy themselves. 

And now... it's just her. Her, by herself, as her companions go off and do honeymoon things. 

At least it's nice to sit here and admire the view. The stars are very bright, and the colors rippling across the sky look like a laser light show. She's sore and tired, but at least she's got a nice, big bed all to herself. She doesn't usually sleep much, but her conscience is gnawing at her more than usual, and a good, long rest usually helps with that.

"Doctor?" 

Speaking of her conscience... 

"Yaz?" The Doctor looks over, to see Yaz walking towards her. She's wearing a big floppy t-shirt with a picture of a cow on it, and has one of the hotel's big green towels slung over one shoulder. 

"Hi," says Yaz, and she takes a tentative step forward. "I'm not interruptin' anything, am I?" She shifts, and she looks faintly self conscious. "Oliver is off playing squash. They've got a good squash court here, apparently." 

"Not at all," the Doctor says, and she sits up, then winces. Her back twangs, and she shifts. "Who doesn't love squash," she adds, mostly to cover up the wince.

"He's the only person I know who plays squash," says Yaz. "You alright?" She comes to sit next to the Doctor on the lounger, and her bare thigh presses against the Doctor's trousers. The t-shirt lifts, and the Doctor can see the bottoms of a red swimming costume.

"Yeah," the Doctor says, and she smiles a bit, self conscious. "I went to get a massage, and the person who was doing it wasn't used to doing a single massage, versus a couple's massage. So all those tentacles, focused on me, they went a little... vigorous." 

Yaz wrinkles her nose. "Ouch," she says, and she puts a hand on the Doctor's shoulder and gives it a squeeze.

The Doctor makes an embarrassing noise - somewhere between a moan and a squeal - and Yaz _doesn't_ take her hand off. 

"You're stiff as a board," Yaz says. "Let me give you a back rub."

"What?" The Doctor looks sidelong at Yaz, frowning. They shouldn't be having this much physical contact - the whole point of this honeymoon trip is to get Yaz and O back together, to put all this... whatnot behind them. 

Yaz isn't playing along.

"Your back," Yaz says, her tone surprisingly patient. "I'll rub your back for you."

"Y'don't need to do that," the Doctor says, but she's weak. She's already melting into the touch as Yaz's strong thumbs dig into the tender spots in her back, circling over the knots. 

"I really don't mind," Yaz says, and the two of them are both dancing around the elephant in the room. 

On the deck, in this case, since they're out by the pool, but... still.

"If you're certain," the Doctor says, but she lets Yaz maneuver her so that she's sitting closer to the end of the lounger, leaning forward. She doesn't even argue as her braces are pushed down her arms, to dangle around her back.

She's just... tired. She's tired and she's lonely, and since Ryan and Graham aren't coming back, she feels like Yaz and O are the only humans she _has_ right now, as herself. Sure, there's all the other humans she knows on Earth, but none of them are _these_ humans, who know _this_ her.

It's one of the amazing things about O. He doesn't trip over the fact that sh used to be a man and is now a woman the way so many other humans do, and Yaz… well, Yaz is one of the only people who's only known her as a woman. 

"You're off with the fairies," says Yaz, pulling the Doctor out of her own thoughts.

"Sorry," the Doctor says, and she's blinking in the dimness. The lights lining the pool are off, and the only illumination is coming from the lights _in_ the pool and the aurora blazing above them. 

"What are you thinking about?" Yaz's thumbs are digging into the Doctor's back, and the Doctor hisses, leaning further forward. There must be some knots in her shoulders - how did the being with all the tentacles miss them? 

"Humans," the Doctor says absently, "and how you lot work."

"Can I ask a question?" Yaz's hand moves to the hems of the Doctors' t-shirts. "Can I take your shirts off?"

"Is that your question?" The Doctor looks over her shoulder, and she catches Yaz's faintly annoyed expression. 

"No," says Yaz, and she's still tugging at the bottom of the t-shirts. "Unless there's some new rule involvin' a question allotment." 

There's a pause. _I feel like I'm missing something,_ the Doctor thinks distantly, but she lets Yaz pull the two shirts up and over her head. She's not wearing a bra, and the sensation of cool air against her nipples makes her tingle, her skin breaking out into goose pimples. 

"I'd tell you if there were any new rules," the Doctor says slowly. Yaz's fingers are ghosting over her back, and she shivers. "I'd think that... some rules are obvious. Since you're engaged now." 

"Lie on your stomach," Yaz says, giving the Doctor a brisk pat on the shoulder. 

_I know a subject change when I hear one,_ the Doctor says, but she doesn't feel like arguing. She lies on the lounger, her arms folded under her chin, and she shivers when Yaz's hands rest on her back.

Neither of them say anything, as Yaz's hands move across the Doctor's back, kneading and pressing to release the tension. The Doctor is trying not to make any embarrassing noises, but it's painful in some spots, and a grunts and gasps escape around the fist she's got shoved into her mouth.

"Y'need to relax," Yaz tells the Doctor, breaking the silence.

"Isn't that partially why we're here?" The Doctor asks, and her voice is only a little strangled, as Yaz finds a particularly rough spot and digs her knuckle in. "Well, we're here so that you and O can try out honeymoon spots, but -"

"You're not very good at relaxing, are you?" There's rustling, and then Yaz is... moving to sit on the backs of her thighs.

Okay. Um. 

She isn't sure how she feels about that, but the warm weight of her is grounding, and the way Yaz is pressing down on her back is pleasantly painful. She's trying not to squirm too much, as the tension is kneaded and prodded out of her. She really shouldn't be letting Yaz do this, should be getting up, maybe sending Yaz back to Oliver. 

Hell, the Doctor should find herself a lover. A proper lover, so she stops falling into bed with the both of them. This is going to ruin their marriage when it gets out, and these sorts of things aren't well hidden, are they?

Especially with the looks that Yaz keeps shooting her. Oliver is at least subtle about it - all those years of spying, even if he claims it's only been from behind a desk. 

"You're tensing up again," Yaz says, and she prods the Doctor in the shoulder.

"I can't help it," the Doctor says, and there's a note of whining in her voice. "It's hard work, being me!"

"You need to let go," Yaz says. "Relax." 

The Doctor rolls her eyes, and then she _gasps_ , because the tips of Yaz's loose hair is tickling along the bare skin of her back, and it's making her wriggle, her toes digging into the lounger's cushion, and then Yaz's hot, wet tongue is passing over the curve of her shoulder blade.

The Doctor's teeth dig into her arm to keep from crying out, and she's trembling, as Yaz presses another kiss next to the spot she just licked. Then there's suction, and Yaz's fingers are digging into the Doctor's shoulders as her mouth moves along the Doctor's back, nibbling and kissing. She's sucking hard enough that there might be marks, and maybe the Doctor is worried about that, but she can't find it in herself to care just then.

_Was I always this sensitive and just didn't notice before?_ She's too dazed to pay too much attention to her thoughts, because Yaz's mouth is still moving along her back, and she can't stop _moving_. Her hips are grinding, and her eyes are squeezed shut. She's gasping as she tries to catch her breath, but she can't seem to breathe, she can't do anything but lie there and take Yaz's hot human mouth as it moves across her back.

There's the occasional pressure of Yaz's blunt teeth digging into the sensitive skin, and then it lets go, and it's more kisses and stroking. She's melting, slowly, and she's going to die of overstimulation, while _simultaneously_ , she's going to die if Yaz ever stops. 

"I've never had you this pliant," Yaz says quiet, and the Doctor can't ignore the undercurrent in her voice. It sounds... pleased, and something else that makes the Doctor's pulse pick up between her legs. 

"Pliant isn't a word that's usually used to describe me," the Doctor murmurs, her eyes drifting shut.

"It's interesting to think I bring something out in you," Yaz murmurs, and the Doctor shivers. The air is thick as honey, and there's a dream like feel to everything. 

"Of course you do," the Doctor says, and she's faintly surprised at how soft her own voice is. 

"You should roll over," Yaz says, and her voice is still soft. 

"Should I?" The Doctor looks over one bare shoulder, and Yaz's eyes are glittering in the dim light. 

"Definitely," Yaz says. "Your back's all done." 

"You'll have to get off of me," the Doctor says, and it sounds a little too much like.. well, she's not sure, but she can smell Yaz's pheromones, and her own arousal is pulsing through her, both hearts seemingly doing double time. 

Yaz gets off of her, and the Doctor misses the warm weight of her already. She rolls onto her back, and her breasts jiggle, then move towards her armpits, and that's still taking some getting used to. Her chest moves so much, and sometimes it's in the way, but... the way Yaz is looking at her is certainly something.

"Y'know, I don't think I've seen this much of you," Yaz says, and she settles herself between the Doctor's legs, then leans forward. She's still wearing the big t-shirt as a cover up, and the hem brushes against the Doctor's bare stomach, making it jump.

"I don't think many people have," she says, and she's very carefully not thinking about sitting in Oliver's lap, his mouth on her nipple, his cock inside of her.

Her cunt clenches around nothing, and she takes a deep, gasping breath. 

“You’re so pretty,” Yaz says, and her hand skates across the Doctor’s belly, her chest. She pinches the Doctor’s nipple, and the Doctor gasps again, her head tilting back. “Are you getting used to this?” 

“A little bit,” she murmurs. “Like a p-pair of shoes. You always end up with… blisters.” Her voice is going a little high pitched, and then she’s losing the thread of whatever it is she was going to say, because there’s hot breath on her nipple, and Yaz’s hot little mouth. 

Yaz’s tongue is flickering over her nipple as she _sucks_ , and she plucks the Doctor’s other nipple, twists it. The Doctor is losing track of everything, it’s all becoming a mess of arousal and guilt, and she’s still staring up at the aurora, the lights reflecting back into her eyes. 

“You’re the most wonderful person I’ve ever known,” Yaz says, staring down into the Doctor’s eyes, and something about that face Yaz is wearing - loving, hopeful, trusting - makes the guilt worse. She breaks Yaz’s gaze, and then she sighs as Yaz’s mouth closes over her nipple again, and tangles her fingers in Yaz’s long, dark hair. 

“I mean it,” Yaz whispers into the Doctor’s breast. She rests her head between them, her breath ghosting across the damp skin - is the Doctor sweating, or is she still damp from Yaz’s kisses? “You’re beautiful, you’re the smartest person I’ve ever known, you’re -”

The Doctor covers Yaz’s mouth with her hand, and she’s aware of how sad her face is - she can feel it pulling her face out of shape. She traces the softness of Yaz’s eyebrows, over the elegant slope of her nose. 

Yaz takes the Doctor’s thumb into her mouth, and she sucks on it, her tongue tracing over the thumbnail. She sucks it into the hot, wet cavern of her mouth, and Yaz is keeping the steady eye contact, as the Doctor’s thumb presses deeper into her mouth. 

_This would be amazing if I still had my cock_ , the Doctor thinks dazedly, as she fucks into Yaz’s mouth with her thumb. _I shouldn’t be doing this._ Yaz pulls off of her thumb. _I don’t want to ever stop._

She’s still staring as Yaz kisses down her belly, hot, wet tongue mouthing at her breast again, then lower, to her belly. She rubs her cheek against the softness, and then she’s tugging the Doctor’s trousers down, taking the boxers with them, and the Doctor hisses at the cold air on her overheated skin. 

There’s an awkward moment, as the Doctor kicks her trousers off, and now she’s spread open in front of this human, and she’s never felt more vulnerable. Yaz is settling between her legs, and she closes her eyes, resting her hand on top of Yaz’s head. The hair is silky against her palm, against the pads of her fingers, and then Yaz’s mouth is moving over her mound, the tip of her tongue is tracing over the Doctor’s clit.

_For all that it’s an evolutionary dead end, I definitely appreciate it_ , some part of her mind gibbers, but most of her is lost in the white hot pleasure dancing through her body, right across her nerves. She opens her mouth in a silent gasp, and then it all seems to crash down on her head.

There are two slim fingers pushing into her pussy, and Yaz is sucking on her clit, Yaz’s hair in her fist. She tosses her head and rolls her hips, her heels digging into the lounger, and she’s trying so hard not to moan out loud. The whole place is next to empty, but what if Oliver comes -

Her cunt clenches tight around Yaz’s fingers at the thought, and Yaz moans, licking harder, sucking harder, her tongue tapping out a desperate Morse code message, and then she’s working her jaw and she’s _sucking_ , and it should be overwhelming, but all it’s doing is making her whole body seize up. She clenches like a fist around the Doctor, and then she groans as she comes, a long, slow pulse that seems to wash over her like a wave.

Yaz licks her through it, fingers moving with the push of her fingers, and her tongue is still moving as the Doctor’s fist unclenches. She looks up at the Doctor, pulling back, and she rests her chin on the Doctor’s mound. Her lips are shiny in the glimmering light of the pool. 

“You taste similar,” Yaz says, and whatever it is she’s going to say next is abruptly too much. 

“I have to… I have to go,” the Doctor says, although some part of her longs to wrap around Yaz, press her face into Yaz’s hair and feel that single human heart. Wouldn’t it be simpler to go to O, tell him? Maybe the three of them…

And then she remembers Bill, trapped in metal. Remembers… all of them, all these people she’s loved, who’ve loved her, who’ve _trusted_ her, and her chest aches. She can’t lose them. She can’t let that… 

Yaz kisses the Doctor’s inner thigh, and then she’s _sucking_ , her blunt little teeth digging in, and the Doctor shudders, her over sensitive cunt clenching around Yaz’s fingers. She sighs, as Yaz’s thumb finds her clit, and Yaz’s teeth dig into the meat of her thigh. 

“I know you can’t feel the way I do about you… to me,” Yaz says, and she kisses the spot she was sucking on. “That’s okay.” She presses her damp hand over the Doctor’s, laces their fingers together, and the Doctor squeezes back. “I’ll be here,” Yaz says, and somehow, that hurts more than anything else she could say. 

The Doctor lies there, still holding on to Yaz’s hand, until the human lets go. Yaz kisses the Doctor on the forehead, and then she’s walking towards the pool. There’s the sound of fabric hitting the floor, and then a quiet splash.

The Doctor sits up, and she watches Yaz swimming laps around the pool. The guilt is at least quieter in the back of her mind, and she’s almost meditative as she gathers her clothes back up. Maybe she’ll go have a soak in the hot tub, do some thinking. 

Can’t hurt to try, at least, right?

-*-

The Master pretends to fumble with the towel around his waist when he walks into the room with the small private pool he, Yaz and the Doctor have use of on this floor and sees the Doctor nestled in the hot tub at the end.

“Shit - sorry Doctor, didn’t realise you were in here. Yaz said you were at the main pool downstairs…?”

“Oh,” she replies, and her cheeks flush a pleasant shade of red. She ducks down a bit further under the bubbling water so that only her chin up is visible. “Yeah. Bit crowded down there.”

He nods. “Well,” he gives an awkward gesture with his hand. “I was going to go for a soak myself, but I’ll come back later.”

“You don’t need to do that,” she says quickly as he makes to turn. He looks back round at her. 

“No?”

The Doctor shakes her head. “Course not. There’s plenty of room.”

“Just… thought it might be weird. You know…” He says, but he’s making towards the hot tub, hands fiddling with the towel. “Considering.”

“Nah. S’not weird. It’s fine! We’re fine. All good!” Her voice is too bright; too cheerful. _Doctor you are so embarrassingly obvious_ , he thinks with some amusement. 

“I suppose… we are both adults,” he agrees. 

“Yeah! That. And friends. We’re still friends, right?”

“Of course we are Doctor.” He gives her an easy smile. “Um. Would you mind just…?” He motions for her to turn around, pointing at his towel in a slightly awkward way he just knew she would find _endearing_ , and on cue, her cheeks go pink again, and she flails a bit, twisting round in the water to face the other way. 

She’s breathing fast, he notes as he drops the towel and takes his time stepping into the hot tub with her, and he can hear her double heartbeat racing from here. She fiddles with the bubbles on the surface, full of restless energy, and the Master settles back against the tiles on the other side, allowing himself a small smile as he sweeps his gaze over hazy bare skin beneath the water’s slightly translucent surface, before he clears his throat. 

“You can turn around again now.”

She does, and her eyes catch his just briefly before she’s ducking beneath the surface, popping up a moment later and slicking her wet hair back off her face. 

“So. Enjoying yourself?” She asks brightly. 

He nods. “Oh yes. It’s beautiful here. Yaz loves it too.”

“Yes, good! It’s one of the only resort planets left in this time period that hasn’t become completely overrun by tourists. I mean - there’s people here, enough visitors to keep the economy going, at any rate, at least there must be because it runs for another fifteen decades yet - but it’s not the easiest to get to - requires a slightly dangerous trip through a small field of asteroids to access the planet’s atmosphere, no way of avoiding it either since the gravitational field of them throws off any teleports within a five hundred mile radius…”

“Unless you have a TARDIS,” He smiles. 

“Yes! Exactly. Comes in handy sometimes, having a TARDIS.”

“A lot of times, I imagine,” he replies smoothly. She’s babbling, which means she must be even more nervous than he’d thought she might. Had she been with Yaz again already? Recently? There had certainly been time, between when he last saw them both and now… He watches her face carefully as she continues on a rambling explanation of the tourist industry in this century. She’s avoiding his eyes, playing with the surface of the water absently and talking much too fast for her to just be excited. He wonders if she and Yaz had fucked by the pool. It had been empty when he’d taken a peep yesterday - although he isn’t sure whether this version of her would be put off by there being people around or not. 

He wonders if she’d come, and how recent it was… he wonders if she’s still wet from it, hot and slick beneath the hot water. He wonders if she’ll let him find out. 

She’s distracted enough by her own words, and doesn’t notice him inching closer as she talks, not until he reaches out, lifting a wet hand from the water and touching a fingertip gently to her cheek. She inhales sharply, words halting mid-sentence. He smiles at her. 

“Sorry - eyelash,” he lies easily, washing the pretend eyelash from his finger in the water. 

“Oh,” is all she seems to be able to come up with in response. 

“That’s my name,” the Master grins. 

He’s still sitting close to her, close enough to feel her hot breath on his lips, and he doesn’t miss the way her eyes jump down to them as he shifts in the water, pretending to bump his knees against hers accidentally then hastily apologising. 

“It’s fine,” she replies, and beneath the water, he drops a hand to her knee, hoping the touch could come across as innocent enough for her not to feel the need to brush him away. 

She doesn’t. 

“You know, I’m glad we came, Doctor.”

Her eyes widen a little. “What?”

“Here,” he stipulates, trying not to laugh. “To this place. I think it's just what we all needed.”

“Oh - yes, yeah me too. I mean I’m glad. That you like it.”

He squeezes her knee. “I do. We do,” he confirms, squeezing again, and he lets his hand drift a little higher. “So thank you.” When he squeezes this time, his hand spans her thigh, fingers just touching the soft skin of her inner thigh, and she tenses beneath his touch, inhaling sharply and holding her breath. Interesting, he thinks. He gives the soft flesh another experimental squeeze and her eyebrows furrow a bit. His eyes drop down, looking through the murky bubbling water. Was that a dark mark on her skin, right by his fingertips? 

“O,” she murmurs, and her eyes are slightly hooded, her breath coming quick. 

“Yes?” He presses his fingers right into the mark, and she gasps, then there’s a sudden flash of an image - it’s her, head tossed back, hands buried in dark hair as she lays on a sun lounger with her legs spread - then the image is gone, and the Master pulls his hand away quickly when she flinches. “Sorry,” he says quickly, and to his surprise, she grabs his hand beneath the water, bringing it back to her thigh. 

She hasn’t realised she’s projected to him - why would she? As far as she’s aware, he’s human, and the dampener on his DNA would prevent her from feeling any of his telepathic capabilities. Oh, he could have fun with this. He wonders what else he can draw from her - wonders if he touched her the way Yaz clearly had just an hour before, if it would spark any vivid flashbacks. 

“No it’s okay,” the Doctor says, then seeming to realise what she’s done the moment she has done it, she lets go of his hand quickly, and pulls back a little, cheeks flushing. “We shouldn’t be…”

“Talking?” He strokes circles on her skin beneath the water, fingers inching higher. 

The Doctor bites her lip, giving him a look. “Are we just talking?”

“Of course we are.” A little higher, and he can feel the heat radiating from her centre, even through the hot water. 

“Your… hand says differently,” she replies, words faltering a bit when he squeezes her soft flesh again. 

Instead of replying to that, he shifts his hand higher, fingers sliding deftly between her legs where, just as he had imagined, he finds her slick and hot like a little furnace inside the water. She exhales shakily, her thighs parting for him. 

“We shouldn’t,” she repeats. 

“We can stop?”

She bites her lip, her eyes closing as he strokes her clit, brow furrowed, and he thinks for a split second that she is going to stop him - before she opens them and pulls him to her, her mouth meeting his. 

He groans into the kiss, biting at her lip as he slides his fingers down and inside her, slipping into her as if into hot butter, her body opening and squeezing at him, welcoming him inside as he kisses her deeply. 

It’s a game - like everything seems to have to be between them, but it’s still _the Doctor_ , and something deep inside the Master that he hates a little is signing with joy as she presses herself close and allows him inside. He’s hard already, and when he curls his fingers up towards himself inside her, he is afforded another of those flashes of memory; two slimmer fingers inside her, a hot little mouth sucking on her clit and the Doctor’s mouth open as white hot pleasure shoots through her. 

A sudden flash of irritation rises inside him, and abruptly he wants to erase all traces of that insufferable human girl from her mind, replace each and every memory of pleasure with him.

He could duck beneath the water - he’s more than capable of holding his breath long enough to bring her off, but that might be a little giveaway as he’s fairly certain humans don’t share their respiratory bypass capabilities. So instead, he breaks the kiss, and shifts in the water, taking hold of the Doctor by the waist and lifting her, straight up and out of the water as she gives a gasp of surprise, sitting her up on the side. 

“O,” she utters, hands on his shoulders as he moves to kneel in the deep tub, positioned perfectly between her legs like this. He glances up to see her wide eyes gazing down at him - and doesn’t miss the way she shifts a hand to rest on one thigh, (un)subtly covering the dark purple love bite there. The other threads into dark hair that’s still dry, her damp hand gripping hold of a fistful of it and tugging his head towards her. 

He doesn’t know if she’s just eager to get his mouth on her, or desperate to prevent him catching sight of the mark he’s already aware of, but he can’t care too much either way, when the gesture brings his face right up against her glistening pink cunt. His mouth waters, and he inhales deeply as he opens his mouth to lick her, tongue tracing up through her folds, opening her up meticulously and carefully, lapping at her until she’s whining softly in frustration. 

He is determined to draw this out; make it better than what she’d just had. Granted, he doesn’t have one of these, but Yaz can tend to go in far too quickly whenever she goes down on him, all rushed inexperience that makes him roll his eyes, and he expects she’s the same with the Doctor. He intends to very much show her how it should be instead of how it was… he’s already done this, but was perhaps a little hasty last time in his eagerness. This time, he’s got all the time in the world, and he wants to tease her until she’s dripping wet and begging him before he makes her come. 

“Tell me what you like,” he murmurs against her clit, lifting dark eyes to hers. Her mouth is open and her hand is tight in his hair, chest heaving, droplets of water trailing down her milky skin. 

“What I like?” She mumbles. 

“Yeah,” he says, and kisses her clit. She gasps, thighs jumping a little. “Do you want my fingers inside you? My tongue… my mouth on your clit…?”

She gasps again, back arching as her head tips back and her feet shift, disturbing the water either side of him. 

“I… I liked what you did last time. I like anything you do. I just - I _need_ …” She tugs at his hair again, and raises her hips, pushing her cunt towards his mouth. 

“I want to make you feel good, Doctor,” he says, making his dark eyes go wide and eager and innocent like O’s. Just the kind of adoring gaze he knew she loves those humans of hers to give her. Predictably, she gives a shudder. 

“You are - you do,” she tells him hastily. 

“I just…” he bites his lip, resting his chin on her thigh just by her hip, looking up at her as he lets his fingers stroke her hips. “I know you probably don’t have much experience with this, since this body’s still new to you and all - or, or maybe you have, I don’t like to assume… have you been with anyone else? - No, that’s inappropriate, forget I asked,” he hastily says, privately delighted by the way she practically _flinches_ at his words. 

He watches her swallow, and she’s shifting, shrinking back a bit like she’s going to pull away - 

He buries his face between her thighs again quickly, mouth open as he kisses her deep and slow right over her core, and as he does he’s afforded another peek into her head - he see’s Yaz this time - or more to the point, _tastes_ her, her familiar flavour sharp on the Doctor’s tongue as she laps at her, her own hand shoved down between her legs, fingers rubbing quick - 

The image is gone, and the Doctor is moaning, her thoughts giving way to sensations instead, and now she’s projecting out him, O, he is everything that’s in her head in this moment now and this was everything he wanted. 

He pushes his tongue into her, wriggling it and licking around her entrance until she’s whining, and then he presses a kiss there, before he nips his way upwards, using his teeth on her just lightly until he gets to her clit and closes his mouth around the hardened little nub and _sucks_. 

“Oh - _fuck_ \- O,” she gasps, leaning back a little, one small hand braced on the marble floor behind her as he sucks at her clit, letting his tongue flick over it rhythmically. His hands grip her hips, and he pulls her tighter against him, sucking at her until she’s gasping, little high-pitched sounds leaving her lips, and then pulling back to blow cool air onto her hot slick folds. 

“Stop teasing me,” she utters, breathless above him, and he slides a hand up and pinches one of her nipples with a smirk in retaliation. Her hand flies up and grabs his wrist, digging her nails in, but she doesn’t pull his hand away from her, and so he rolls her nipple between his thumb and forefinger as he laps at her, pinching every so often and listening to her gasp. 

Yaz had sucked on her nipples earlier. He suddenly knows this very intimately, when a vivid flashback hits him hard. She is really _awful_ at projecting when she’s turned on, it seems. Yaz’s mouth had been small and hot around her nipple, her tongue flicking at her just like his had done over her clit, and a suddenly flash of irritation flaring in him, he pinches her hard again, enough to make her yelp, and yank at his hand. Her eyes are wide when he glances up, and she looks annoyed - but a fresh rush of wetness has pooled between her legs, and she’s not thinking of Yaz anymore, anyway. 

“Sorry,” he forces himself to mumble against her, kissing her clit by way of apology. “Got carried away.”

“It’s fine,” she pants, “Just… hurt.” Her hand cups her breast, and the Master stands between her legs, water streaming from him, nose running up over her stomach as he rises so he is eye level with her chest standing in the deep jacuzzi. He wraps her thighs snuggly round him and leans in, moving her hand away to kiss the offending nipple gently, listening to her sigh as he does so. She tilts his hips, grinding herself into his torso, and he can feel her hot wet core sliding over his abdomen. 

“O please,” she breathes as he sucks gently on her nipple, then nips at the underside of her breast. He presses one last kiss there, before placing a hand in the middle of her chest and nudging her. 

“Lay back then,” he orders, and she does so, collapsing onto her back on the cool marble floor, and gripping tightly to the edge of the jacuzzi as he bends to bring his mouth to her cunt again. 

He pressed his fingers into her this time, and she keens, and then he’s pumping into her hard, steady and purposeful now, the teasing flicks of his tongue replaced by a firm rolling motion over her clit that has her gasping and her hands scrabbling for purchase on the slippery floor. 

A flash of long dark hair twisted in her fists, and he shoves a third finger into her, fucking her with them until she doesn’t have the capacity to think anymore. Her orgasm is loud and beautiful, her thighs shuddering either side of him, water splashing as she lifts her legs, and back arching on the cool marble floor. He doesn’t give her time to come down from the climax, persisting in the hard rhythm of his fingers, sucking on her clit relentlessly until she’s twisting and shaking again, cries echoing in the empty room. 

She’s still shaking when he pushes her up fully onto the floor, shifting her sideways so she’s laying parallel to the tub as he clambers out on his own shaky legs to cover her body with his. 

He’s so ready to slip straight inside her, when she places her hands on his chest and pushes at him, shaking her head. 

“We shouldn’t, O,” she mumbles, cheeks pink and chest heaving. 

Frustration flares in him and he wants to yell - want’s to grab her hands and pin them above her head and drive into her anyway, fuck her like he knows they both want - but he can’t. He’s O, and he can’t. 

“We… but we just -”

“I know but… this feels like too much.” She pushes at him again, and twists out from beneath him. 

He stares at her back, his jaw slack, own chest heaving and cock absolutely _throbbing_ he isso achingly hard. He opens his mouth to speak - to say something - _anything_ that could persuade her to let him finish this properly without coming across as too forceful - but she’s already getting to her feet on slightly wobbly legs, hastening to grab one of the white towels on the bench at the side and wrapping it quickly round herself. 

“I’m - I’m sorry,” she says, avoiding his eyes. “I’ll… - I should go.”

The Master watches with an open mouth as she hurries out of the pool room and away from him, leaving him unsatisfied, aching and alone. 

Furious, he drops back into the hot tub, grasping his cock in his own hand and bitterly rubbing himself until he comes, uncaring about contaminating the water.

**Notes for the Chapter:**

> Always wanted to go swimming somewhere I could see the aurora. One of those bucket list goals.


	7. Chapter 7

**Notes for the Chapter:**

> Do you like anal? Because this chapter has anal.

Yaz finds her fiance sprawled out on their bed when she gets back to the room, skin still tingling and hot from the hot shower she took. She’s still buzzing with arousal, but he looks so comfy like that, his eyes shut, the sheets pushed down around his hips. He’s wearing a pair of purple boxers, and the sheets are tangled around his thighs.

She’s still aroused, an anxious energy crawling up and down her back, filling her whole body like a static. She can still taste the Doctor on her tongue, can still feel her whole body on edge. She… isn’t sure what she wants, since she’s currently not even sure what she’s feeling emotionally, but she’s showered, and she’s not sure if she wants to masturbate or sleep or… what. 

She climbs into the massive bed, and he rolls towards her, a mountain range shifting across the continental shelf. One of his hands go to her hip, and he snuggles up to her, one leg going to drape over hers. 

“Hi,” he murmurs, and his voice is rough and creaking with sleep, which makes her heart ache for the way she’s betrayed him.

She doesn’t say anything, she just leans forward and kisses him. It’s a gentle little brush of lips on lips, and she can taste the mint of his toothpaste. His breath is hot against her mouth, and his eyelashes flutter against her cheek. 

“Were you dreaming?” Yaz’s voice is quiet. The room is very _big_ , and it seems like all of their words are being swallowed by all the furniture and all the empty space. 

“I don’t think so,” he says, and his hand moves from her hip to slide up her shirt. He presses down on her belly, and then further, to cup her breast. 

“Somethin’ got you all worked up,” she murmurs, and then he’s on top of her. There must have been an in between phase, but it’s almost like a film being played in fast forward. One moment he’s beside her, then he’s on top of her, and he’s kissing her, his mouth wet and hot and insistent. 

He’s so _heavy_ , and she sighs into his mouth, her fingers tangling in his hair. It’s so different from kissing the Doctor - he’s musky, and his hair is shorter, his jaw covered in stubble. She’s comparing the one to the other even as she’s kissed, and she doesn’t know how to turn that off. She should. She really, really should. 

_Enjoy the one you’re with_ , she tries to tell herself, as he kisses up her neck, his stubble leaving her abraded as sandpaper. He’s warmer than the Doctor, and his heart is beating so hard against her chest she can almost imagine that he’s got two hearts himself. 

He’s almost savage, as he kisses down her neck. There’s the nip of teeth and then he’s sucking - _I’m gonna have one whopper of a hickey_ , she thinks dazedly, and then she remembers the hickey she left on the Doctor’s thigh, and she moans hard enough that her whole chest vibrates. 

“Fuck,” he mumbles, panting in her ear. “You were… you were asking me what set me off, but you -”

She grabs his hair, pulling his mouth back to her own, and then she’s rolling the both of them over, her knees digging into his sides as she’s straddling him. Her shirt is still shoved up around her chin, and she wriggles out of it, tosses it aside. Her breasts hang down, and then more of his stubble rasping against the delicate skin of her breasts. His teeth dig into the side, and it’s harder than he’s ever bitten her before.

Her cunt clenches around nothing, and she’s grinding against his stomach, her pussy wet and hot in her shorts. She cries out when he bites her, and he bites her again, a little harder this time. 

“Get these off,” he says, hooking his fingers in the elastic and pulling them roughly down. She has to pull her knees off of him to kick them off, and then she’s being rolled onto her back again, and he’s on top of her, a presence like a nightmare crouching on her chest. 

His hips slot between her thighs perfectly, he way they always do. He doesn't ask how she's so wet, as he kisses down her body. His teeth are a blunt pressure on her breast, his tongue a ticklish contrast as it swirls over her navel. She _squeals_ when he sucks a hickey into her thigh, thrashing on the bed. 

He eats her out like he's mad at her, with a fervor she's never experienced before. 

At least, not from him. 

She's reminded of the Doctor's own desperate licking, and she grinds down on his face - or tries to. His hands are holding her in place now, pinning her to the bed as his tongue fucks into her and his rough cheeks abrade her delicate vulva, her tender inner thighs. 

At least he doesn't ask her why she's already so wet, as he licks it up from her, then latches on to her clit. He sucks in deep pulses, then pulls away right when she's about to come. 

This is nothing like her usual sweet, thoughtful lover. He's… kind of being an asshole, honestly, as he climbs back on top of her. His mouth is on her neck, biting down, then sucking. There's a sharp flash of pain at the same time as his cock is shoved into her, and she isn't sure what it is that makes her come, and yet. 

He moans as she flutters and pulses around him, holding himself up on his forearms as he fucks into her with a desperate, frantic pace. She bites the other side of her neck, and she rakes her nails down his back. She doesn't miss the way his cock twitches when she does that, and she angles her hips up so that bis pubic bone is grinding against her clit as he pounds into her. 

He fucks her like she's offended him, like he has to prove something to someone, and she's giving as good as she's got, her nails in his sides and her teeth in his shoulder. He's going to have bruised calves from her heels digging in, and her neck is going to be one big bruise. 

He comes in her with a groan like he's been stabbed, and she shoves her hand between the two of them to rub her clit into a quick, desperate flash of an orgasm. He makes a pained noise at the way her cunt squeezes his over sensitive dick, but his touch is gentle on her face. 

"So," he says when he catches his breath, "I'm thinking this might be a good honeymoon spot?" He sounds like his usual self, and whatever anxiety was coiling in the base of her gut eases. 

"Could do," she agrees sleepily, and she sighs when he presses another kiss to her bitten up neck. 

She isn't sure how she feels about… well, everything, but it is comforting to know she can always come back to O. That she can always rely on him.

It really is good to have a certainty in the world, and she tries to keep that in mind as she runs her fingers through his sweaty hair. 

-*-

"So," says the Doctor, "what did you think of the resort?" She's dashing around the TARDIS, full of nervous energy. 

She's very much _not_ looking at the marks on O's back peeking out under the collar of his shirt, or the bruises on Yaz's neck. 

"It was very nice, Doctor," says O. "Thank you."

"D'you think that'll be your honeymoon spot?" _Focus on that idea, focus on taking them on their honeymoon, focus on the fact that they're together, that they're in love, that they're getting married._

"I dunno," says O, his expression thoughtful. He's got his thumb hooked into Yaz's belt loop, and she's leaning into him, her head on his shoulder. They both look very tired. "I liked it, but..."

"But?" The Doctor looks at them expectantly.

"I like the idea of going someplace less... known," says O. "Less built up."

"Oh no," Yaz says, but there's good humor in it. She disentangles herself from him, goes to lean against the console. "Every couple of months he gets the idea into his head that he wants to go camping."

"I don't just get the idea into my head," O grumbles, and he moves closer to Yaz again. She takes another step back, and the Doctor tries not to watch the little dance play out. She's not sure who she's jealous of, and she's not even sure if she's jealous or not.

"Let's have some time at home first," Yaz says, then she glances shyly over at the Doctor. "You're welcome to visit," she adds, almost as if it's an afterthought. She looks faintly embarrassed, and the Doctor wants to take Yaz's sweet human face into her hands. "Not that we don't love traveling with you, Doctor, but I miss my bed."

"We can't exactly complain that we didn't get a chance to relax," O says, and he sounds almost... chiding. 

"Well, yes, alright," Yaz says. "I just wanna go home for a bit, that's all. Get into the groove of things again." She shoves her hands into her pockets, and she looks faintly uncomfortable. "It's easy to just fall into the excitement, when we're traveling, but we _do_ have a real life back home." 

"Of course," the Doctor says, and she's smiling. She can feel her whole face doing it, and that must make it real, right?

"You're always welcome," says O, and his expression is so open and warm that it makes her stomach twist up. 

"Thank you," the Doctor says, and her voice is only a little bit choked up. "It's... appreciated." She clears her throat. "It's been lonely," she says, and she means it. "Without you lot. I miss you when you're not around. Or when I'm not around, I suppose, although I can't be not around when I'm by myself, since you're always with yourself, obviously, but - "

She is cut off by a pair of arms around her. Two pairs of arms - the two humans are holding her tightly, keeping her in place, and she probably should be pushing them away, be telling them this was a bad idea, that they need to give her space, that... what? 

It isn't as if they _knew_. If they knew they'd say something, and neither of them has said anything. If this was like something in a movie (not even a pornographic movie, just one made maybe fifty years after their time) they'd all get together, the three of them as one unit, and it would be lovely and perfect and...

She lets herself be held, ignoring the way her mind is shouting at her to tell the truth, and she tries not to let the jealousy that's nibbling on the edges of her mind, boring through her hearts. 

She lets them hold her, and she is warmed by their feverish, human lives. 

-*-

Oliver looks at the Doctor from his open door, looking faintly surprised. "You're early," he says.

"Am I?" She frowns. "I said the thirteenth, didn't I?" 

"It's the third," says O. At least he doesn't look mad. "Well," he adds, "Yaz isn't in." There's a pregnant pause, as if everything is holding its breath. "You can still come in, if you'd like," he adds. "She's working an overnight, so she'll be home late."

"Why's she working so late?" The Doctor comes in when he steps aside, tries not to think about the way his eyes are so bright, the way she's seen his face before. 

"Oh, y'know how it is," he says. "She's still new. D'you want a beer?" He pauses. "Do you drink?"

"I drink plenty of things," she says, mainly to tease. Then she grins. "Yeah, I drink beer, if that's what you're askin'. Although it doesn't have the same impact on me." 

"D'you actually _like_ it?" O is in an old pair of jeans and a sweater that looks like it's starting to get thin around the elbows. He looks so _comfortable_ that it makes her want to hold him close and bury her face in his neck, to clutch at his sweater and press herself closer to him. She wants him to wrap his arms around her, wants to feel his human warmth and his heartbeat. 

"I like a lot of things," she says haltingly, and that's an awkward thing to say, isn't it? She clears her throat, kicks her boots off, and goes to flop on the couch. 

He sits next to her, beer in hand, his legs stretched in front of her, and the look he's giving her is so _soft_. How does he always manage to make her feel so... warm? So safe? It's almost like he knows her better than she knows herself, and there haven't been many humans that she's felt that bond with. 

"It's still slightly... surreal, having you here," he says, looking at her, and she can see from his eyes that he's still slightly foggy from the alcohol. It also looks like the scratches on his back have healed up, judging by the bits of his shoulders she can see from the neck of his shirt. 

"Is it?" She blinks at him, trying to wrap her head around his words. 

"Yeah," he says, and he rubs the back of his neck with one hand. He looks... sheepish.  
“I liked you for a long time - back when you were a man.”

She tilts her head at him curiously. “Really?” 

O nods, then he looks embarrassed, running a hand through his hair. “Actually, uh…” he gives a chuckle. “You were the first woman I ever, uh…”

He trails off, but the Doctor catches his meaning and her eyebrows shoot upwards. “I was?”

Another nod. “Honestly, I’d always thought I leant strictly the other way. But then you were there - like this - and you were you and… well. It didn’t matter that you were a woman now.”

The Doctor feels herself soften. _Humans_ , she thinks, fondly musing that it was one of the sweeter things she’d heard. 

“Still forget to think of myself that way sometimes, if I’m honest,” she replies.

“As a woman?” 

The Doctor nods.

“That’s understandable. Spending so long as a man, I suppose…” he trails off, looks like he’s going to say something else, then leans forward to take a sip from his drink instead.

She tilts her head at him. “What is it?”

He swallows his mouthful of beer. “What’s what?”

“Whatever it is you were going to say.”

O chuckles. “You’re very intuitive aren’t you?” There’s some look across his face for an instant, but then it’s replaced with beery sleepiness. 

She smiles, shrugging one shoulder. “I’ve been told that a few times.”

“I uh…” He laughs - she thinks he’s nervous - and drags a hand over his face. “I was just going to say that. Well. You know… this… is a bit different with a man.” He gestures between them and she raises an eyebrow. 

“Do you mean sex?”

“Sex, yes,” he confirms, blushing. “I was just wondering… do you miss it? How it used to be, I mean -” he fumbles over his words. 

“Are you asking if I miss the er…” she points at her crotch. 

“No!” O splutters, cheeks going even redder. “No, no - well - yes, I mean that too I suppose, I just meant… well you’ve mentioned being so many years old and you seem to know your way around these things and I just _meant_ -”

“O.” The Doctor places a hand on his arm. “Just spit it out.”

“I meant do you miss having sex as a man - on the recieving end. Specifically. With a man. Unless I’m totally wrong and you’ve only been with women before and - oh, I’m messing all of this up.”

Chuckling softly, she shakes her head, finally catching on to what he was dancing around.  
“O,” she says. “Is this your very roundabout way of asking me if we can do anal?” She’s faintly shocked at how… blunt she being, but how can she not be, in this intimate little moment? 

He turns even redder at that - and he does look so very pretty blushing, she thinks. 

“Um. No - yes? If - only if - it’s just… Yaz won’t let me, and I just -”

Her eyebrows raise at that. “She won’t?” 

O shakes his head. “She says she doesn’t like it. And you know - I’d never pressure her or anything. This thing between us… just sort of happened, after you left - and Yaz is brilliant, she really is -”

“Yes she is,” the Doctor interjects quickly, meaning it, and trying not to think about the fact that what she was doing here with O would hurt her if she ever found out, or how O would be hurt knowing what she's been doing with Yaz -

“But, I don’t know. Sometimes I miss it, I suppose. But I understand totally if you don’t want to, I just thought -”

“I do.” It tumbles from the Doctor’s lips before she’d barely thought about it. Her cheeks heat up a bit, and arousal pools in her belly and settles between her legs as her hearts speed up in anticipation. _Yaz won’t let him_. The fact rings in her mind, and spurs on her drive to do this - something O wants to do that Yaz can’t give him. And Yaz said that she would do anything for the Doctor, that she loved the Doctor more than anyone in the universe... She tries not to dwell on what any of that means. 

“You do?” O’s face is lighting up, surprised delight shining in his dark eyes. 

“Yeah, I mean - I’m fine with it. You’re right, it wouldn’t be the first time for me. Well - in this body technically it would be but - yeah. Yes. We can do that.” She wipes sweating palms on her trousers, tries to come off as casual even as she’s already practically throbbing between her legs with want now. “Got any lube?” She’s never been one for going slow, has she? But why not. 

“I - _oh_.” O hastily sets down his drink. “You mean right now?”

“Sure. Unless you’d rather -”

“No! Now’s fine. Now’s… great.” He glances at the clock, then nods. 

“Great!” She repeats, and jumps up to her feet. She’s very carefully not thinking about the fact that Yaz won’t be home for hours yet. 

-*-

It’s chilly in O and Yaz’s room, and the bedsheets are cool against her skin as she relaxes into them, her face on a pillow and her chest pressed to the bed while her hips are raised, weight on her knees. 

She groans as O presses into her, two fistfuls of the pillow in her hands, and despite the cool air, a little sweat has started to build at the back of her neck. She hears him give a groan of his own, one hand braced on her backside and the other on the bed beside her where he’s draped over her back. 

It feels good. Better than she’d expected, to be honest. It had been rather a long time since she’d taken a cock this way - her last self not having much interest in these sorts of things, and she’d sort of thought it would be… lacking, now that she was a woman. But the way her body stretches open, the fullness she feels as O presses in and the heat of his body over her warms her from the inside and makes pleasure hum right down to her core. 

“You good?” He checks, his voice thick with arousal. 

“So good,” the Doctor replies, and he gives a chuckle and strokes a hand up over her back as he shifts, so he’s kneeling up behind her. The hand slides down over her sides, fingers brushing her breasts, and strokes across her hip and thigh before wandering down between her legs. She feels him shift, leaning down a bit to get the angle, and the Doctor gasps at both sensations at once as he moves inside her just as his fingers find her aching clit and glide over it. 

Her hips jolt, pushing back against him, and she arches her back to bear down and back against the pressure as O strokes her there. 

“Move,” she mumbles into the pillow, panting. “ _Please_ -”

He does, and it’s bliss. His fingers quickly lose their rhythm then leave her altogether so he can brace his hands on her hips, and the Doctor shoves her own hand down between her legs to replace them instead as O starts rocking inside her. 

He’s so deep within her that she can hardly breathe with it, and she feels almost unbearably full yet empty at the same time. Whimpering, she presses two fingers inside herself, then three, letting the heel of her hand grind against her clit as she fucks herself in time with O’s movements. 

Neither of them last very long. She’d have almost been embarrassed at how quickly she comes if it didn’t feel so _incredible_ , and if when she’s got done moaning she didn’t feel O’s hips jerking into her, gasps and exclamations of pleasure falling from his lips as he comes inside with a cry of her name. 

_My name_ , her mind chirps contentedly as he slips out of her with a wet sound. She slumps down on her stomach as O flops to his back next to her, and both of them lay panting for several moments. 

She chastises herself for the thought as she lays there next to him, but she cannot quell a little bubble of something within her that hummed with smug contentment at her having given O something he wanted that Yaz couldn’t. It was a terrible thought, and she loathes it as much as it gives her sick satisfaction. Loathes it as much as she loathes herself in this moment, but it warms her as much as the familiar body cuddled up to her. Trying not to dwell on it, she turns her head to look at the man laying next to her, catching his eyes, and finding herself matching the lazy grin he gives her. 

“Well,” he says after a moment. “That… was over a little quicker than I’d have liked.”

His cheeks are tinted pink, and the Doctor laughs softly, shifting onto her side and shuffling forward, swinging a leg over his. 

“You really did miss it, hm?” She teases, and he wraps an arm around her, reaching down and squeezing a handful of her bum. 

“So did you from the feel of it.”

“Touche,” she replies. She’s a little sore but she won’t deny that she enjoys the feeling as she curls into O. She’ll dwell on her guilt later, when his breath isn’t dancing across her face and his single heart is thudding against her shoulder.


	8. Chapter 8

Yaz lies sprawled out on her bed, kissing the Doctor like it's the end of the world. It will be the end of the world, when Oliver finds out about this, and really, the fact that Yaz is so at peace with this is probably a sign of how far gone she is. How much they should stop. 

The Doctor’s mouth finds the soft, delicate spot by Yaz’s ear, and her hair ticklish along Yaz’s neck. One hand skates up Yaz’s bare side, and Yaz squirms, whimpers. Then she _squeals_ , as the Doctor’s fingers find the ticklish spot along her ribs. 

The Doctor pulls back, one eyebrow up. “That’s a new one,” she says. “Never heard you make _that_ noise before.” 

“I make a lot of noises,” Yaz says, faintly self conscious. “Sorry, I’m just… really ticklish.” There’s a wet, sweaty spot under the small of her back. She’s going to have change the sheets, or else Oliver might notice. 

Why do they keep doing this in the bed she shares with him? She should be on the TARDIS, with its abundance of empty rooms. They can literally fuck into next week and there won't be any chance of Oliver ever noticing. 

In theory. 

But she's still gasping and moaning as the Doctor kisses down her naked body, while her fiance is off at his doctor's appointment, and the Doctor had made a joke about that too, about how she was having her own Doctor's appointment. 

The Doctor's hot mouth (somehow still hot, even when the Doctor's body is so much cooler than Yaz'a own) closes around Yaz's clit, and Yaz gasps, closes her eyes and lets the pleasure roll over her. How is the Doctor so _good_ at this. Other than being super old, obviously. 

The Doctor, for her part, seems utterly absorbed in her task. She sucks and licks, her tongue moving smoothly across Yaz's vulva, swirling over Yaz's clit. 

Yaz squirms when the Doctor’s tongue quests a little lower. “Doctor,” she says, and her voice is shaking, just a little, “what are you doing?”

“Wanted to see what other noises I could make you do." The Doctor bats her eyelashes and gives her cheekiest grin, then bends her head down lower, beginning to gently lap at the seam of her labia. 

“That… _oh_!” Yaz’s hips jerk forward, and she squeezes her eyes shut, her head thrown back. The Doctor’s tongue is tracing along the spot O had pressed the head of his cock against the other night, right around her asshole. 

“Do you trust me, Yaz?” The Doctor is staring up at her, all big, hazel eyes and pink cheeks. Her blond hair is mussed from Yaz grabbing it, and she keeps eye contact as her tongue probes again. 

“I… I do,” Yaz says, and she’s still trembling as the Doctor’s tongue delves in a little deeper. “That isn’t… that isn’t a thing I do, though, it’s…” She loses her train of thought, as the Doctor’s tongue goes deeper, her thumb rubbing across Yaz’s clit. The pleasure is skittering across her nerves, leaving her trembling.

“Why not?” The Doctor nips Yaz’s thigh - gently, so as not to leave any marks - and then the tip of one finger is pressing against Yaz’s arse, and Yaz hisses through her teeth.

“Thought… thought it were kinda gross. P-p-pornographic.” Yaz gasps as the Doctor’s finger sinks into her, thick and bony. “I don’t… want to be th-th-that kinda… _fuck_!”

“D’you want me to stop?” The Doctor curves her finger, but stops pushing it in. “I can, if you’d like?”

“I…” Yaz can’t think, as the Doctor’s finger slowly moves inside of her. The Doctor’s tongue is on her clit again, and oh, that’s too much, it’s all overwhelming. She lets her legs spread wider, and the Doctor moans, and presses closer. She’s still fully dressed, and that makes it _dirtier_. 

The Doctor showed up, fully dressed and wild eyed, and then she’d made sure that Oliver wasn’t due home for a few hours, and had shoved Yaz into bed. And now Yaz is having her arse fingered open, after she hadn’t even let Oliver touch her there.

She sobs as she comes, her hips jerking forward awkwardly and her toes curling against the Doctor’s sides. She makes eye contact, and if she didn’t know better, she’d think that the Doctor was… smirking. 

“Was I.. .did I do well?” Yaz isn’t sure why she’s so shy, as the Doctor presses a dainty little kiss to her clit. Was that the right thing to ask? It feels like an odd thing to ask, when _she’d_ been the one who was receiving the pleasure. 

The Doctor presses a kiss to Yaz’s belly. “You did excellent,” she says. “Good girl.” She nuzzles her face into the softness, and Yaz runs her fingers through the blond hair.

The Doctor sighs, and she relaxes into the touch. “You did it well,” Yaz says. “I mean. Is there, like. A proper thing to say after a time like that?” 

Yaz gently tugs at the Doctor’s hair, and the Doctor moans. “Nope,” the Doctor says breathlessly. “The orgasm was p-p-probably a good sign… oo, Yaz, a little harder?”

Yaz gives another yank “You make me come _so_ good,” she says, and her cheeks are getting hotter. “So well? Is that the proper name way of saying it?” The unspoken words are on the tip of her tongue. _Better than Oliver,_ she doesn’t say. “I can’t believe I’m thinkin’ about grammar right now,” she says, and she’s blushing harder. The guilt is heavy and thick in her gut, like a brick or an anvil. 

-*- 

Screw all his elaborate, universe-destroying plans, _this_ is the most fun the Master has had in a long while. 

It definitely makes the eighteen months spent here on earth, building this dull and boring life (lie) with Yaz worth it. Every second of it. Besides - she’s not completely intolerable. She was bright - for a human - and the character he’s constructed for O gets on easily with her. Sometimes it’s easy to just drop into him - become O for a little bit, while the Master sits up in the back of his own mind, often elsewhere. Two places at once - he’s clever like that. 

But then the Doctor had finally come back, and she’d played _right_ into his hands… it was almost too good, watching her struggle with herself. Watching her lose a little piece of her damn morality every day. She’d have a hard time keeping her righteousness after _this_ whole shebacle… perhaps she could excuse what she was doing with one of them - talk herself into some ridiculous lie of needing the closeness and contact or whatever rubbish she told herself - but there was no way she could excuse fucking _both_ of them.

Quite honestly, he isn’t sure why she had fallen into bed with the two of them so readily, but he expects a lot of it is rooted in jealously which is just _perfect._ The Doctor! High and mighty and good and kind and all that nonsense, jealous of two human lovers. She wanted both of them for herself and when suddenly she felt that simultaneously slipping away… she cracked. It was glorious.

Every moment of it. Moments like _this_ especially. 

He’s got the Doctor on her stomach beneath him again, in the bed he and Yaz share (which couldn’t be more perfect, he thinks with amused satisfaction), when his phone rings from the bedside table.

Usually he’d ignore it at a time like this. But when a glance over shows _her_ name lit up on the screen, the Master just cannot resist.

“Hang on - sorry -“ he pretends to fumble, pausing his movements and stretching over to grab for it. “It’s Yaz - if I don’t answer she’ll wonder why and she’ll only keep calling - hey!” He says the last word into the phone after pressing answer. “Everything okay?”

“Hiya,” comes Yaz’s voice. “We’re quiet tonight, they let me off early.”

_Damnit,_ he thinks. And good thing he answered - he’s having way too much fun with the situation to end it preemptively by Yaz walking in on him and the Doctor already. 

“Yeah? That’s good - so - so you’re coming home now?” 

The Doctor twists her head round at his words, wide eyes locking with his. 

“Just leaving the station. Just wondered if you want takeaway? I can grab it on my way?”

“Oh - food. Yeah, yeah, that would be good,” he enthuses, eyes still on the Doctor’s. She was stopping to get food, which meant they still had time. He moves his hips just a little, rocking into the Doctor, who gives a soft gasp in response. 

“You alright?” Comes Yaz’s voice down the line.

“Yeah! Yeah fine uh - what were you thinking? For dinner?”

He’s moving now, pumping into her steadily again, and he can see her mouth fall open, see the way she wrestles with herself on her face, knowing how bad this was but enjoying it all the same. 

“Umm I was thinking either Chinese or Indian? Unless you wanna try that new pizza place that opened, Gary from work said they went there the other night and it was really good, pretty cheap too apparently…”

He tunes out her words, wondering why it was that humans seemed to have a horribly irritating habit of telling their significant other every single minute detail of their boring lives. He lets his eyes sweep over the curved line of the Doctor’s spine instead, gaze settling on where he’s thrusting inside her, watching as his length moves in and out of her, her body pink and shining with slick where it grips his, soft flesh ripping with his movements…”

“O?”

“Huh? Sorry - yes, yeah whatever you want baby.”

The Doctor twists her neck again at his words, mounting ‘ _baby?’_ At him with a frown. He shrugs, hoping he looks suitably embarrassed as he tries not to laugh. He adds a twist of his hips on the next thrust for effect, and the Doctor’s face flushes with pleasure. _Perfect._

“So you don’t mind?”

“Uhh…” he tries not to groan as he feels the Doctor’s cunt clench around him. There’s a smile on her lips he can just see from the side of her face where she lays her cheek on the pillow again, and he knows that was deliberate. _You want to play that way, he thinks, game on._

“No I don’t mind. You can decide,” he tells Yaz into the phone, then he props it between his ear and his shoulder and shifts, hoisting the Doctor’s hips up with both hands so she’s up on her knees and he’s kneeling behind her. She gives a gasped squeak at the movement, and Yaz’s irritating stream of chatter pauses down the line. 

“Are you alright?”

“I’m fine,” he tells her smoothly, sliding a hand down and round beneath the Doctor’s hips so his fingers can slide over her. “So, takeaway?”

“Yeah - shall we do pizza then? What one do you want? We can share but I don’t want anchovies. You know I hate them…”

_God, she was annoying._ His fingers slip over the Doctor’s clit as Yaz natters in his ear, and he gets great satisfaction by watching her struggle to keep quiet. 

“... pop to Tesco’s as well, I think we need milk?”

“Yeah, yeah good,” he mutters distractedly into the phone.

“Can you check?”

He shoves a bit deeper into the Doctor. “Now?”

“Yes now. Don’t wanna go all the way there for no reason…”

_Oh for…_ he lets out a choked gasp as the Doctor squeezes him inside herself again, and loses his rhythm.

“O?”

“Sorry!” He quickly says. “Uh - yeah we do! No milk!”

“Are you… what are you doing?”

There’s a hint of suspicion in Yaz’s voice and that just won’t do. 

“Working out,” he lies smoothly. “Just,” he gives a groan as he shoves particularly hard into the Doctor. “Doing my push ups for the day..”

Yaz snorts, and he can hear the sound of her getting into her car. “Since when do you work out?”

“I work out,” he replies. “Sometimes.”

“Sometimes?” Yaz teases.

“Sometimes, yes…” he bites his lip, considering. The Doctor is soft and pliant beneath him, and she’s so _wet_ and open… he runs his palm over her cheek, spreading her open, and she sighs and arches into it… “Sometimes I like to… _push_ myself…” as he speaks, he slips out of her hot cunt, and takes himself in his hand, pressing the tip of his slickened length to her arse, and sinking inside her before she can react.

She gasps, loudly, and he hastily shoves her face into the pillow before she can make another sound as he buries himself inside her, biting down so hard on the inside of his cheek so as not to make a sound himself he draws blood.

“... training together if you want? You know I’ve been trying to get you to come running with me at the weekends for ages.”

Gods, how was she still talking? This had been fun, but he’s almost tempted to hang up on her so he can focus fully on how incredible the Doctor feels around him and fuck her properly. He lets her up for air and she turns her head to the side, panting open mouthed into the pillow.

"Maybe," he says, and he circles his hips, pressing himself as deep as he can get. She’s so tight around him, and his eyes are crossing as he grips her hip. "Oh, actually," he adds as his hips go still, "could you pick up more lube? Think we're running low."

He can almost hear her blush from the other side of the phone. "We can't be," she says, and there's a bashful giggle in her voice. Humans and their ridiculous sex hang ups. "Have we been -"

"It's all the travel," he says, reaching under the Doctor with his free hand to pass over her clit with his thumb. "You know how worked up I get, how good it feels to be in our own bed together again, after. And I think we left the other bottle in the TARDIS."

"So who knows when we'll see it again," Yaz agrees. "The way the Doctor talks about the TARDIS, it might be offended that we brought it in the first place."

The Master doesn't need to see the Doctor's face to know it's all caught up in annoyance at her beloved TARDIS being besmirched like that. He removes his thumb and drapes himself over her back, pinning her with the weight of his body and tickling her back with his chest hair. 

"I think the ship likes watching us," the Master says, as if he's saying something conspiratorial. "I'll let you go so you can start driving."

"Dunno how I feel about the TARDIS watching me like that," Yaz says, and she gives an exaggerated shiver. "See ya in a bit, love you!"

"Love you too," the Master says, as he forces his cock a little deeper into the Doctor. He likes the way her whole body flinches when he says it. 

He hangs up and drops the phone. Then he's thrusting into her again, at full force. She grips his cock tightly, and she's crying out as he takes her, almost as if it hurts. He's going to leave bruises in her hips, and he wonders, distantly, how she's going to explain that to Yaz. 

He feels when she comes- a psychic shockwave that burrows its way down into his gut, and he forces himself as deep into her as he can get as he comes, throbbing like a star into the tight heat of her arse. 

"Fuck," the Doctor says thickly. She grunts as his dick slides out of her, grimaces at the sensation of his wet come dripping out of her asshole. 

"Give us a minute," the Master pants, and he flops himself down onto the bed beside her. "Not as young as I used to be. And Yaz is due in soon."

"Oh," she says, and he can _feel_ the guilt emanating off of her, like standing next to a hot stove. 

"How about you pop into the shower," the Master suggests. "I can tell her that I was doing my exercise, you'll be out before she gets back."

The Doctor is tense underneath him, but she nods. "That sounds like a good idea," she says, and then she cranes her neck to kiss him, a sweet little peck. 

He kisses her back, and he's smiling against her mouth. Let her think it's because of the orgasm, and not his delight in all the chaos he's provoking. 

She _has_ always been dull like that. 

-*- 

When the Doctor comes into the living room with wet hair, she finds a sweaty O sitting on the couch next to Yaz, who is still in her work clothes. sweaty O and Yaz, still in her work uniform. Only her centuries of practice keep her face from giving away her panic. 

“Doctor,” Yaz says, and wow, she is _not_ a good liar. Her whole face opens like a flower when she sees the Doctor’s face, and if O weren’t so _trusting_ he’d probably suspect something. 

“Hullo, Yaz,” says the Doctor. She goes to sit on the chair by the coffee table, which has an open box of pizza.

“Oliver told me you stopped by because the TARDIS is in a mood,” says Yaz. “Not letting you have a shower?”

“Yeah, exactly,” says the Doctor. “She keeps turnin’ me hot water cold. I buzzed up Oliver and asked if I could have a quick dip in your shower, while the TARDIS gets over her tantrum.”

“Now that it’s free, you can go have one,” Yaz says, nudging O in the side. “You stink!”

“First you’re after me to get up and exercise,” Oliver complains, but it’s an easy, familiar sort of complaint, “and now you’re after me because I did.”

“I’m glad you exercised,” Yaz says quickly. “But go shower, before you scare the Doctor off.”

The Doctor helps herself to a slice of pizza, the gooey cheese leaving a long, stringy trail from the box to her hand. “I’ve smelled worse,” she says confidently. “Did I ever tell you about the skunk people?” 

Yaz snorts, and she leans back. The Doctor tries not to let her eyes linger. This was fine. Totally fine. A hang out between mates.

She shifts in her seat, and there’s a sharp pain in her arse. _Oh_. She just has to… ignore that. Ignore it, and she’ll be fine. 

Absolutely fine. 

-*-


End file.
